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2021 Fantasy Baseball Third Base Sleepers

As the cold winter months loom, it means we are closer to spring. Closer to pitchers and catchers reporting, closer to Spring Training, and closer to Major League Baseball. Commissioner Rob Manfred has told teams to prepare for a normal start to Spring Training and a 162 game season. You know what that means; it’s time to prepare for Fantasy Baseball. Its time to dig deep into the draft board and find those third base sleepers.

Here at FantraxHQ, we have been working hard since October to prepare you for Fantasy Baseball draft season. In-season management is a huge part of winning, but knocking your draft out of the park will carry you a long way. The key to winning your draft is not necessarily hitting on the early-round picks but rather finding the right late-round sleepers. Today we will dive into some third base sleepers to help you win your drafts!

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2021 Third Base Sleepers For Fantasy Baseball

Austin Riley, Atlanta Braves

2021 ADP: NFBC: 225.9 | Fantrax: 258.4

Let’s kick off our third base sleepers with a former highly regarded prospect who has struggled with swing and miss. Austin Riley brings huge power to the table. I mean, he can obliterate a baseball. After mashing in Triple-A to begin the 2019 season, Riley was called up from Gwinnett to Atlanta. In his first 18 games, he hit nine home runs and posted a .324/.368/.732 slash. The hype was crazy, but unfortunately, it did not last. Many saw the decline coming, especially given his 32.9 percent strikeout rate over those 18 games.

The rest of the season was not kind to him. Over his final 62 games, Riley struck out nearly 38 percent of the time and slashed just .192/.249/.379.  He still managed to hit for power, hitting nine home runs over those 221 plate appearances. The power was one of the few positives to take away from the rough stretch.

There were several positives to take away from Austin Riley’s 2020 season as well. When glancing at his line of .239/.301/.415, you may not be overly impressed. Riley’s power also seemed to be zapped, hitting just eight home runs in 206 plate appearances. But, Riley did make a notable drop in his strikeout rate, down to 23.8 percent. If he can manage to keep his strikeout rates between 20 and 25 percent, he has a much higher chance to be an everyday player.

Riley chased fewer pitches out of the zone in 2020 while also increasing his O-Contact rate by over six percent. He significantly improved his zone contact rates as well, jumping from 73.7 to 83.3 percent. His overall contact rates were also up nearly ten percent. A huge improvement from what we saw in 2019. His swinging-strike rate of 14.8 percent is still dangerously high, but nothing compared to his 20.5 percent rate in 2019.

Despite not showing huge power in home run numbers, Riley still had an average exit velocity of 91 mph, better than 82 percent of hitters. His average launch angle was also much improved, down to 13.6 degrees. His hard-hit rate was 42.9 percent, and he had an expected batting average of .262. All positive signs.

Even if Riley is just a .250 hitter in 2021, he will likely hit over 30 home runs, given the Braves’ commitment to playing him every day. At his current draft price between 225 and 250, Riley is an easy buy and option among third base sleepers.

Edwin Rios, Los Angeles Dodgers

2021 ADP: NFBC: 329.8 | Fantrax: 344.3

Edwin Rios got his act together before the 2020 season by getting into great shape and proving his doubters wrong. Rios once attended metabolic camp in 2015, or what he would call “fat camp.” He lost 20 pounds in 30 days, and it has been a challenge to keep it off ever since. It has forced him to work hard, and in 2020, he was determined to come into Spring Training in the best shape of his life.

I know we laugh about the constant “best shape of their lives” quotes every spring, but Rios was. He was more athletic. His defense at third base improved. He was able to tap into his monstrous power more often.

In a limited sample of just 83 plate appearances, Rios slashed .250/.301/.645 with eight home runs. This is coming off a 2019 season where he hit 31 home runs and slashed /270/.340/.575 in 444 plate appearances in triple-A

There are some holes in his swing, though. Even in his strong 2019 Triple-A season, he struck out 34.5 percent of the time. The strikeout rate was surprisingly low at 21.7 percent in his small 2020 sample. But did he really improve?

Rios chased 36 percent of pitches out of the zone and made contact just 41.9 percent of the time. His overall contact rates were a putrid 64.6 percent. His whiff rate was also 17.7 percent. Those stats show his poor plate discipline.

Rios did post impressive statcast data, with a barrel rate of 13.6 percent and an average exit velocity of 91.5 mph. His launch angle was a solid 14.5 percent, and his hard-hit rate of 45.8 percent showed his power. The question is, can he make enough contact to put the power to use.

As things currently stand, Edwin Rios is projected to be the Dodgers’ everyday third basemen. That could change quickly if the Dodgers make a trade or sign a free agent, but Rios is slated to get at-bats. He will get a chance to prove he can handle the hot corner for the World Series champs. At his ADP, Rios is a nice option among third base sleepers. He is a nice source of late-round power and shouldn’t kill you in batting average.

Ke’Bryan Hayes, Pittsburgh Pirates

2021 ADP: NFBC: 136.7 | Fantrax: 171.9

Is Ke’Bryan Hayes still considered a sleeper? It may be a stretch. But based on his Fantrax ADP of 171.9, it seems like many are not buying in. Some had soured on Hayes as a prospect, but he proved the doubters wrong in his small cup of coffee in Pittsburgh in 2020.

Hayes came up and slashed .376/.442/.682 with five home runs and a stolen base. He was well documented for his hit tool and speed in the minors, but the questions came about his power. Each year, Hayes seemed to add power, but the five home runs in just 24 games surprised many.

He hit the ball extremely hard, with an average exit velocity of 92.8 mph. His hard-hit rate of 55.4 percent was also very impressive. Sure, it was a small sample, but Hayes showed the ability to hit the ball very hard. If these trends continue, Hayes has a chance to be an elite player. Why?

Ke'Bryan Hayes Sleeper

The contact rates that Hayes posts are elite. While it was a small sample, his zone contact rate last season was 96.1 percent. If Hayes had qualified, he would have ranked first just a tenth of a percentage point ahead of David Fletcher. Hayes’s overall contact rate of 83.6 percent would have ranked just 20th. But, none the less, Hayes can hand his hat on the fact that he posts elite zone contact rates.

Suppose Hayes can continue to hit the ball hard with elite contact rates. His stock will soar. The question remains, how legit is his power? 20 home runs annually would not surprise me. Tack on a solid hit tool and great speed, and you have the makings of a great asset for Fantasy Baseball.

Even though his ADP is higher than most on this list, I still think people are sleeping on Ke’Bryan Hayes. He is among the best third base sleepers.

Third Base Sleepers For Deep Leagues:

Luis Urias, Milwaukee Brewers

2021 ADP: NFBC: 396.9 | Fantrax: 382

Luis Urias was one of the most advanced Minor League hitters when he was traded from the Padres to the Brewers. Many Padres fans were even upset when the team traded Urias and Eric Lauer for Trent Grisham and Zach Davies. Now, Brewers fans likely wish they had Grisham and Davies back.

Regardless, there is still a lot of untapped potential in Urias, who is just 23 years old and makes elite contact rates. In Triple-A in 2019, he hit 19 home runs, stole seven bags, and slashed .315/.389/.600 in just 339 plate appearances. There is an intriguing profile here and much of his 2020 season can be dismissed to having COVID-19. At the draft price, Urias is worth the gamble and a great option among third base sleepers.

Carter Kieboom, Washington Nationals

2021 ADP: NFBC: 453.2 | Fantrax: 362.9

Another former top prospect, Carter Kieboom has failed to live up to the hype. In 165 Major League plate appearances, Kieboom has managed to slash just .181/.309/.232. When you post an OBP that much higher than your slugging percentage, you are struggling. Kieboom has managed just two home runs over that time span.

Kieboom still has upside, and his draft price is meager, especially on NFBC. As of right now, Kieboom is the favorite to be the everyday third basemen for the Nationals. I believe with time, Kieboom will gain his footing and be a solid third base option. Maybe never elite, but Kieboom can be solid. If you are in an OBP league, it only makes Kieboom more intriguing among third base sleepers.

Isaac Paredes, Detroit Tigers

2021 ADP: NFBC: 556.5 | Fantrax: 490.1

Isaac Paredes was unimpressive in his Major League debut with the Tigers in 2020. The good news is, he is just 21 years old and has a solid Minor League track record. Paredes brings a great hit tool and approach to the table. He is a patient hitter who walks at a high rate and does not strike out often. There is some untapped raw power in the tank as well. Check out this bomb he hit in the Liga Arco. There is a lot of talent in the Tigers system coming up that can play third base, but it is Paredes’s job to lose for now. You also have nothing to lose at his ADP by taking a late-round stab at a potential sleeper.

I hope you have found these third base sleepers useful. Best of luck this season, and win your drafts!

Media Credits: Baseball Savant, Fangraphs

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  1. BB says

    Sorry to be nitpicky, particularly since I really enjoy Chris Clegg’s work, but it seems like fantasy writers across all sites are increasingly confusing whiff rate with swinging strike rate. Whiff rate is the percentage of total swings that result in misses; swinging strike rate is the percentage of total pitches that result in swings and misses. So in Rios’ case, a whiff rate of 17.7 percent wouldn’t be all that bad, i.e. one miss out of every six swings. But that was actually his swinging strike rate – one swing and miss out of every six pitches seen – which is pretty dismal.

    1. Chris Clegg says

      Hey BB, Thanks for the comment. It was my fault switching back and forth between Savant and Fangraphs and just labeling them wrong. Thanks for pointing it out.

      1. BB says

        Appreciate the response – you obviously know the difference but it does seem lots of writers are using the terms interchangeably (particularly with pitchers), which can be confusing. Keep up the good work! (And fingers crossed for Rios, have him in one of my leagues.)

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