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2021 Arizona Diamondbacks Top Prospects for Dynasty Leagues

Over the last few years, the Arizona Diamondbacks have become one of my favorite systems to write up each offseason. They have quietly dominated in the draft and international markets while adding talent via trade as well. Most notably, their new ace Zac Gallen, whom they acquired from Miami in 2019 in exchange for Jazz Chisholm. All the talent they’ve accumulated recently has made this top-20 very dynamic throughout, but also has created some difficult decisions. Several of the players that just missed would make a lot of other organization’s top-20s. But still, I’m very excited to kick off these 2021 team by team prospect rankings with my Arizona Diamondbacks top prospects for dynasty leagues. A trio of elite outfielders will start us off.


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Arizona Diamondbacks Top Prospects For Dynasty Leagues

1. Kristian Robinson, OF

There has been some debate recently as to which exciting outfield prospect is the top dog in the Arizona organization. For me, it’s still Kristian Robinson for fantasy purposes by a hair. The 6’3 Bahamian outfielder has flashed exciting tools throughout his time as a professional but is far from a finished product. Robinson’s plus or better raw power has been his calling card so far. He’s finished with one of the top estimated flyball distances in both of his minor league seasons to date, finishing well over 300-feet in both seasons, but a near 50% groundball rate has limited his in-game power to date. There’s also a high level of athleticism here with Robinson and current above-average foot speed.

That 25+/15+ upside makes him one of the more intriguing prospects in the minors for fantasy purposes, but there are some concerns here as well. Mainly, the hit tool. Robinson was at the Diamondbacks alternate site this past summer and I heard from more than one person that there were legitimate issues making consistent contact. He’s shown the ability to draw walks just fine (10.6%), but he’s going to need to make more consistent contact and keep the strikeouts in check (26.3%) if he wants to reach his lofty upside. While I’ve dropped him a few spots in my overall rankings, Robinson is still a bonafide top-15 overall prospect for dynasty leagues.

2. Corbin Carroll, OF

Right on Robinson’s heels is the speedy Corbin Carroll. Ranking Carroll largely hinges on where you think his power is at and what it can develop to in the future. There were reports that he was showing more raw power this summer and that his power future value could be 50-grade. If that is indeed the case, Carroll would move ahead of Robinson and into my top-10 overall. Why? Well, that would put Carroll at 60-hit, 50-power, 70-speed which is basically the same as C.J. Abrams who is currently my #7 overall prospect for dynasty leagues. That plus hit tool and elite speed alone give Carroll plenty of dynasty value. He’s basically Xavier Edwards or Nick Madrigal with more power upside. That’s pretty damn enticing.

After being selected 16th overall in the 2019 MLB draft out of Lakeside Highschool in Seattle, Carroll excelled in his 31 Arizona League (Rookie) games and 11 Northwest League (Short-A) games, slashing a combined .299/.409/.487 with 18 extra-base hits, two home runs, and 18 steals in 19 attempts. On top of that, Carroll had a 15.6% walk rate and 22.0% strikeout rate. Carroll’s swing from the left side is fluid with plus bat speed, but doesn’t generate a ton of loft. His ability to cover the entire plate and spray line drives to all fields is exceptional, and once he gets on base, forget about it. Carroll is a double-plus runner with a high baseball IQ and baserunning acumen. That’s a dangerous combination.

For now, he’s still just a hair behind Robinson for me, but if those power gains show up in game action this season, he’s going to take over as the top dog in this system. The upside here is off the charts and his price tag is only going to rise from here.

3. Alek Thomas, OF

Ever since the 2018 draft, I’ve been one of the highest in the industry on Alek Thomas. Through his first 170 games as a pro, Thomas has slashed .312/.385/.455 with 62 extra-base hits, 12 home runs, and 27 steals with a solid 9.8% walk rate and 18.3% strikeout rate. Outside of a 23-game sample size as a 19-year-old in the Class-A Advanced California League, Thomas has hit above .300 at every single level thus far while being relatively young for each level as well.

But while the stats have been impressive, there are some things I’d like to see improve in this profile. With the swing, Thomas is a bit busy with the hands pre-pitch and can create a deeper hand load because of it at times. The bat speed is plus but I’d love to see less hand movement going forward. And on the bases, while Thomas is a plus runner, he’s only been successful on 62.8% of his attempts so far. With all that said, Thomas projects as a 55-hit, 55/60 speed outfielder with sneaky power that could put him in the 15-18 homer range annually and maybe low-20’s at peak. While everyone is chasing Robinson and Carroll, you can likely get Thomas at a fair price via trade in dynasty leagues.

4. Seth Beer, 1B/OF

You’ve heard the saying “better real-life player than fantasy”, well, Seth Beer is a better fantasy player than real-life as 105% of his value comes from his bat. Beer likely should be a DH in the long run as he’s a well below-average defender, but for now Arizona will find a spot for him either at 1st base or a corner outfield and hope that the DH is adopted permanently in the National League. Regardless, Beer’s bat will get him into the lineup, maybe even at some point in 2021.

After a stellar collegiate career at Clemson, Beer hasn’t stopped hitting in the minors, slashing .294/.388/.508 across 189 games with 38 doubles and 38 home runs. Literally all of his value comes from his bat as he’s not going to provide any speed, but both the hit tool and power grade as above-average here with .280/25 upside down the road. Beer has also shown exceptional zone awareness and doesn’t chase much junk outside the zone. While he was at Clemson, Beer walked 180 times (20.5%) to only 98 strikeouts (11.1%) and has kept his strikeout rate under 20% in the minors (19.5%). Although, his walk rate has dipped to 8.6%. Beer’s bat is legit and should carry him into Arizona’s lineup later this year, especially if there’s a DH slot.

5. Geraldo Perdomo, SS

Valuing Geraldo Perdomo for dynasty leagues comes down to how much stock you put in a player’s power. Outside of power, Perdomo is a top-notch prospect that projects as above-average to plus with his other four tools. He’s shown that in the minors with a .278 AVG, .411 OBP, and 66 steals in 236 games. And while defensive skills don’t show up on our fantasy teams, they still are significant, especially when talking about shortstops or catchers. “Can this player stay at shortstop” is a common question that gets asked. With Perdomo and his plus defense and solid throwing arm, that answer is a resounding yes.

When it comes to his impact at the plate, he has the tools to become a healthy contributor in the AVG, OBP, and SB departments. Perdomo has displayed above-average or better contact skills with a quick and compact swing and all-fields approach from both sides of the plate. While he makes solid contact, his swing is more geared for line drives and the raw power is below-average anyway. Because of that, I’m not sure we ever see him surpass 8-10 homers annually. However, Perdomo’s contact skills, borderline plus speed, and phenomenal plate approach (16.3 BB%, 14.3 K% in MiLB) are tailormade for the top of the order where he could be an annual .280/.380/25 SB threat while scoring a ton of runs as well.

6. Blake Walston, LHP

As I mentioned in the intro, the Arizona Diamondbacks have accumulated a ton of pitching talent over the last few years. Out of their current contingent of pitching prospects, the one I’m the highest on is 2019 first round pick, Blake Walston. When you’re searching for a breakout prospect arm, Walston checks off a lot of those boxes.

Firstly, he’s a 6’5 left-hander with a ton of physical projection left on his frame. There’s always that chance he maintains a Chris Sale type of figure, but assuming he adds bulk, that could push his fastball higher than plus territory. The pitch currently sits in the low-90’s and can touch the mid-90’s with solid armside run thanks to his lower 3/4 arm slot. Added velocity could make this pitch a 70-grade monster if he’s able to sit mid-90’s and touch the upper registers, especially when you factor in Walston’s above-average command of the pitch.

Outside of the heater, Walston throws three secondary offerings with his majestic low-80’s curveball projecting as the best of the bunch and an easy plus offering with great horizontal and vertical break. Walston will also mix in a slider and changeup that both project as average to above-average Major League offerings with the changeup featuring solid fading action. With this type of arsenal, command, control, and projection, Walston could realistically bloom into a #2 starter at the highest level with low ratios and a near 30% strikeout rate. Go get him in dynasty leagues right now before his price tag skyrockets. I can’t stress this enough.

7. Bryce Jarvis, RHP

Although he went to the rival of my UNC Tarheels, Bryce Jarvis is a pitcher I’m quite high on moving forward. That’s not something I likely would’ve said before his breakout final season at Duke. Or should I say, breakout four starts in an abbreviated 2020 NCAA season. In those six starts, Jarvis allowed only 11 hits, two walks, and two earned runs in 27 innings while striking out 40. But four great starts don’t make a ranking. What does is Jarvis’ dynamic arsenal along with his command and control profile.

At 6’2/195, Jarvis isn’t the biggest guy around, but routinely pounds the zone with his low to mid-90s fastball that ticked up once he added some bulk in the end of his tenure at Duke. Offsetting that is a trio of secondaries that all could be above-average to plus offerings in time. Both his curve and slider feature good break in the high-70’s and mid-80’s respectively and can be used as out pitches. Jarvis’ changeup might just be better than them both with great velocity separation, fade, and sink making it a plus offering.

When you have this type of arsenal and the ability to locate and mix mitches well while limiting the free passes, this usually equates to a very effective pitcher at the Major League level. While all your league mates are clamoring about the bigger, sexier SP names in your FYPD, waiting for another round or two to nab Jarvis could wind up being highly beneficial.

8. Jeferson Espinal, OF

Without question, I’ve been one of the higher rankers around on Jeferson Espinal, but I like the profile and upside for fantasy purposes here. It all starts with his hit tool and speed. After signing out of the Dominican Republic in 2018, Espinal debuted in 2019 and impressed from the start. In 56 games between the Dominican Summer League and the Arizona League, Espinal slashed .347/.413/.437 with 26 steals and a pair of home runs while walking 9.3% of the time. That AVG and speed looks great, but we can’t ignore the fact that he was also caught 10 times as well. It’s nice to see that level of willingness to run, but he’s going to need to be more efficient on the bases moving forward.

Another area Espinal will need to improve to become a viable fantasy option is his power. Currently, Espinal grades out as  30 or 40-grade in the power department, but there is some available projection here. Even if he adds bulk to his frame and drives the ball in the air more, we’re likely looking at a power ceiling of around 10 home runs. But if he can get to that level while maintaining his solid bat to ball skills and patience at the plate, there’s a chance he develops into a .275/10 hitter with a decent OBP and 25-plus steals thanks to his plus to double-plus speed. He’s definitely one to watch in 2021 and could be a big riser if the power develops at all.

9. Luis Frias, RHP

After not pitching at all in 2017, Luis Frias has steadily been rising up prospect rankings ever since. Impressive, since he was signed as a 3rd baseman out of the Dominican Republic back in 2015. In each of the last two seasons, Frias posted a sub-3 ERA and saw his strikeout rate jump from 25.4% in 2018 to a robust 32.7% in 2019. His three above-average to plus pitches can be thanked for that. At 6’3/180, Frias has a sturdy frame and electric arm speed that allows him to pump in mid to upper-90s gas with good movement. But with that said, his delivery is high-effort and can lead to bouts of wildness at times.

Whenever you see high-effort deliveries like this, the words “bullpen risk” usually dance around in the back of your brain. While that is an option, the Diamondbacks are going to give him every chance to remain a starter where he could develop into a mid-rotation arm. Frias possesses plus curveball and above-average split change, both of which can generate plenty of whiffs, and will mix in a fringe slider as well. There’s no doubting the electric stuff the Frias has, but it’s his command and control, both currently a tick below-average, that will ultimately determine just how valuable he can become.

10. Corbin Martin, RHP

Arizona Diamondbacks Top Prospects

It took every ounce of energy I had not to rank Corbin Martin higher. On stuff alone, he’d be up pushing the top-5 overall in this system. But as we know, stuff can only take you so far. Describing Martin is easy. Plus stuff, scary command and control. And not scary in a good way either. When you watch Martin pitch, it’s pure filth with his fastball, curveball, slider, and changeup all grading as above-average or plus. However, as I eluded to, Martin’s command and control both grade as below average and limit the overall effectiveness of each offering.

The command is the one that worries me more. You could make a case that Martin’s control is fringe-average and he posted a respectable 8.1% walk rate in the minors, but his inabilities to hit his spots along with his injury history could force Martin to the bullpen down the road. If that does happen, Martin has the electric and filthy stuff to succeed in a late-inning role. I’m not saying that’s going to happen in 2021, but its definitely a distinct possibility. If the command improves, Martin would jump several spots in these rankings.

11. JB Bukauskas, RHP

Arizona Diamondbacks Top Prospects

Much like Martin, JB Bukauskas would greatly benefit from improved command and control. At his best, Bukauskas features three above-average or better offerings in his mid to upper-90’s fastball, sharp slider, and changeup with good fading action. Those pitches allow him to dominate in any given outing, when and if his command and control will allow him to. In 161.2 career minor league innings, Bukauskas has pitched to a 4.06 ERA, 1.41 WHIP, 12.7 BB%, and 27.3 K%.

I’d love to sit here and tell you that Bukauskas was going to develop into a high-K mid-rotation starter. And while I think that is still on the table, the likelihood of that happening is rather slim. Bukauskas just can’t sustain longterm success and turn over a lineup multiple times with his below-average command and control. If I had to place a bet, I’d bet on Bukauskas moving to the bullpen, possibly in a late-inning role.

12. Slade Cecconi, RHP

Arizona Diamondbacks Top Prospects

Even after adding Bryce Jarvis with their first pick of the 2020 draft, Arizona dipped into the collegiate pitching pool once again with their second pick, selecting Miami right-hander Slade Cecconi. While Cecconi didn’t have a stellar career at Miami when you look at his ERA, the big 6’4 right-hander impressed with a plus fastball/slider combination and his ability to miss bats regularly. He’ll also mix in a curveball and changeup, both of which could be Major League average offerings but need some refinement.

The upside with Cecconi isn’t on par with the arms ranked above him on this list, but there’s a solid floor here as a potential inning-eating #4 type of starter that can provide respectable ratios and around a strikeout per inning. If Cecconi can make gains with his curveball and changeup, developing into a back-end #3 starter isn’t completely out of the question.

13. Wilderd Patiño, OF

If you’re looking for a name outside the top-10 that could rise into the top-5 of this system by 2022, Wilderd Patiño would get my vote. The 2017 signee out of Venezuela is one of the better athletes in the entire system with plus to double-plus speed leading the way as his most notable tool. Patiño wasted no time putting that speed to good use in the minors in both 2018 and 2019, swiping 20 bags in 74 games. He’ll need to be a bit more selective, but there’s 25+ steal upside here, maybe more.

How highly Patiño climbs up rankings in 2021 and beyond will be up to how the bat develops. So far, he’s displayed average to slightly above-average raw power and does have some projection left, but a linear swing path and higher groundball rate have suppressed that power in games. With his bat speed and raw power, I could see Patiño growing into 15-18 homers annually, but he’s going to need to drive the ball in the air more consistently. His fringe-average contact skills ticking up would also help. There’s some solid breakout potential here.

14. Pavin Smith, 1B/OF

I’ll admit, I’ve never been too high on Pavin Smith. The contact skills are rock-solid and he’s shown he can draw walks and limit his strikeouts, but first basemen with average power just don’t warrant a high ranking in my eyes. On top of that, Smith has never posted a flyball rate above 37.6% and has been more of a line-drive hitter than one that’s going to assault outfield bleachers.

His performance in the minors so far has fit that profile extremely well. Through 294 games, Smith has slashed .281/.364/.426 with an 11.6% walk rate and a 12.2% strikeout rate. That approach is phenomenal but then you see that he’s only hit 23 homers over those 294 games and your excitement dies out a bit. With his contact skiils and patient approach, I can see a path to Smith becoming a low-end regular, but .280/15 from first base doesn’t move the needle much in fantasy.

15. Levi Kelly, RHP

Arizona Diamondbacks Top Prospects

An overslot 8th rounder in 2018, Levi Kelly has steadily been ascending prospect rankings ever since he was drafted. In 26 starts spanning 106.1 innings, most of which came in the single-A Midwest League in 2019, Kelly has posted a 2.03 ERA, 1.09 WHIP, 9.5% walk rate, and 30.6% strikeout rate. If we had a 2020 minor league season, there’s a good chance Kelly would’ve made it up to Double-A, setting himself up for a potential late-2021 debut. That’s unlikely now, but Kelly is definitely a name on the rise.

But with that said, I wonder just how much of an impact he can make at the Major League level. Kelly has a filthy slider that’s easily plus, but his fastball is above-average at best, and I’ve seen some 50-grades put on it recently. He also mixes in a split-change, which flashes average, but he’s going to need to be more consistent with it. We could be looking at a back-end starter or a middle reliever, especially if he can’t fully develop a 3rd pitch.

16. Matt Tabor, RHP

Every list feels like it has a safe but boring arm somewhere in the last quarter of the list. Matt Tabor is that guy in this Arizona top-20. Armed with three average to above-average pitches, Tabor has excelled thus far in the minors, posting a 3.02 ERA, 1.09 WHIP, and minuscule 4.4% walk rate.  The strikeout rate hasn’t been great overall, but did tick up from 18.2% to 26.8% in 2019. If he can maintain the gains in K rate, that would be great, but Tabor is more of a back-end starter moving forward regardless.

17. A.J. Vukovich, 3B

When it comes to A.J. Vukovich, the name of the game is power. The Diamondbacks selected the hulking 6’5 third baseman in the 4th round of the 2020 draft and potentially got a great value there. Vukovich has a powerful right-handed swing that produces plenty of natural loft and possesses easy plus raw power, maybe even a tick above plus. He even moves fairly well for his size and could add in a handful of steals annually as well. But the real question surrounding Vukovich is if he’ll make enough consistent contact to capitalize on his power upside.

At present, Vukovich’s hit tool is below average with chase concerns piled on top, but if he can get to a fringe-average hit tool and hit in the .250-.260 range to pair with 25+ homers and a few steals, that will definitely play. The ceiling is a Major League regular, but improvements need to be made to reach that level.

18. Liam Norris, LHP

Arizona Diamondbacks Top Prospects

As you’ll hear commonly with young pitchers, Liam Norris has big breakout potential if his command and control can improve. Selected in the 3rd round of the 2020 draft as a North Carolina prep arm, Norris is a big 6’4 southpaw that has already flashed three pitches that project as above-average or plus long-term. Those are his low to mid-90’s fastball, curveball, and slider. You could even see that fastball jump into the mid-90’s sitting range in the next year or two as Norris has some room on his frame to fill out. He’s also shown a good feel for both of his breaking balls and can generate whiffs with each.

But as I mentioned to start, both his command and control are below average, and his changeup needs refinement to reach 50-grade. The good thing is that Norris is still very young (won’t be 20 until August), and has plenty of time to work on these areas of concern. If the changeup improves and command/control comes along, watch out. This is a name to target now in deeper dynasty leagues due to his breakout potential.

19. Stuart Fairchild, OF

Stuart Fairchild was one of the more difficult prospects for me to rank in this top-20. And honestly, he almost didn’t even make it. With below-average power and a swing that doesn’t generate a ton of loft, Fairchild reaching more than 10-12 homers annually in the Major Leagues seems unlikely. That means he’s going to need to hit for average and steal bases, both of which he can certainly do, but to what extent. Fairchild has shown an average to slightly above-average hit tool in the minors with around plus speed, but he didn’t run much in 2019 (13 attempts in 109 games) and was caught in over half of his attempts.

Longterm, a .270/10/20 ceiling isn’t out of the question, but I question if he gets to that level or even fits into Arizona’s long-term outfield plans due to the elite trio we started this top-20 with above. Fairchild is a solid all-around player outside of power, but a change of scenery would do him wonders.

20. Blaze Alexander, SS

Arizona Diamondbacks Top Prospects

This has to be one of the most misleading names in baseball. You’d think that with a name like Blaze Alexander, there would be at least plus speed in this profile. Nope. Alexander is actually around average as runner and might be better suited for 3rd base than shortstop longterm. Don’t let those 24 steals in 152 games fool you. This is more of a 8-12 steal guy than one that exceeds 20 every season. If shifted to the hot corner, his rocket arm and above-average to plus raw power would fit nicely.

Alexander will need to do a better job accessing that raw power in games though if he wants to stick as an everyday player at the Major League level. Peak ceiling Alexander could be a 45/50-hit, 55-power, 50-speed shortstop or third baseman, but he’s going to need to make consistent contact and not pull the ball well over 50% of the time as he’s done in the minors so far.

Honorable Mention

Dominic Fletcher, OF | Jake McCarthy, OF | Tommy Henry, LHP | Jon Duplantier, RHP | Spencer Brickhouse, 1B | Alvin Guzman, OF | Tristin English INF/OF | Andy Young, INF | Drey Jameson, RHP

Media Credit: Chris Clegg, Chris Welsh, Kiley McDaniel, PitcherList


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1 Comment
  1. Helmut says

    Tristin English – must have info; please write up

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