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Staff Roundtable: Who is the #4 SP in 2021 Starting Pitcher Rankings?

With the 2020 season in the rearview, the focus of the fantasy community has shifted into 2021 prep mode. Early rankings are coming out fast and furious with plenty of top starting pitcher rankings among them. Within basically every starting pitcher rankings is a discernable top three of Jacob deGrom, Shane Bieber, and Gerrit Cole in some order. The real discussion starts at #4 and that’s why we’re here today. With several viable options for that #4 spot in starting pitcher rankings, several of the FantraxHQ MLB writers give their takes on who they would rank at #4 in 2021 starting pitcher rankings. Let’s see if there are any common answers.

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Who Should Be #4 in 2021 Starting Pitcher Rankings?

Eric Cross (@EricCross04) – Trevor Bauer

This is a tough question and one I’ve already changed my mind about in the last couple of weeks. My initial thought when compiling my 2021 SP rankings was to put Yu Darvish in the #4 spot. Well, that’s not the case now. Darvish is still my #5 SP for 2021, but Trevor Bauer has now slid into that #4 spot. Why? Well, Bauer was just better in 2020 and I’m a believer in the adjustments he made this season which bumped his spin rates up on all of his pitches.

Pitch2019 Spin2020 SpinDifference2020 Spin Rate Rank
Cutter264029082682nd (Burnes)
Slider273629412053rd (Hahn, Buehler)

All of Bauer’s five pitches saw massive spin rate increases and four of those ranked in the top-3 for spin rate for that pitch. The results followed suit with Bauer posting a career-best 1.73 ERA, 0.80 WHIP, 5.1 H/9, and 12.3 K/9. Every single one of Bauer’s pitches posted an xBA of .201 or lower and all but his sinker has an xwOBA under .250. Furthermore, his four-seamer, curveball, slider, and cutter all had putaway rates above 23% and the last three pitches all had whiff rates well above 30%.

That dominance carried over into the wildcard round as well with Bauer tossing 7.2 shutout innings, allowing only two hits while striking out 12 in the Reds 13-inning 1-0 loss in game one.

Bauer had all of his pitches working for him this season. And to put the cherry on top of this sundae, Bauer also showed better command and control than he ever had in his previous eight seasons. I’m not saying his command and control pre-2020 were bad, but he did cut his walk rate from 9.0% in 2019 to a career-best 6.1% in 2020. His previous best was 7.8% in 2018. Bauer was nearly as good as Shane Bieber this season and can easily replicate that next season if these gains we saw in 2020 continue in 2021.

Chris Clegg (@RotoClegg) – Luis Castillo

SP4 might be the most interesting debate for Fantasy Baseball in 2021. The top three seem clear with some combination of Jacob deGrom, Shane Bieber, and Gerrit Cole. If you were wondering, that is my top three in order, for what its worth. After that, it seems you can go with ten different pitchers in the fourth spot. I ran two Twitter polls to try and determine who others thought should be the fourth starting pitcher off the board. In order, the top vote-getters were Trevor Bauer, Yu Darvish, and Walker Buehler.

I think there are several players who you could make an argument for in the fourth spot. But for argument’s sake, I am going with a player that many likely will not. That player is Luis Castillo. Castillo is just 27 years old and has steadily improved each of the last three seasons. In 2020 he posted a career-high in strikeout rate at 30.5 percent and saw his walk-rate drop by nearly two percentage points to 8.2 percent. His final line for 2020 ended with a 3.21 ERA, a 1.23 WHIP, and 89 strikeouts in 70 innings.

Hitters posted a high BABIP on Castillo at .329 which signifies some bad luck given the league average of .290 and the fact Castillo has a career .275 BABIP against. This factor led Castillo to have an impressive 2.65 FIP, good for fifth-best in baseball.

Luis Castillo pitched like an ace in 2020 without getting ace results. He saw an increase in velocity which led to improved results on his individual pitches. He also made a personal catcher connection with Curt Casali. In six starts with Casali, Castillo pitched to a 1.33 ERA. In the Reds playoff game on Thursday, Casali was unavailable, but Castillo still pitched well striking out seven and allowing one run in 5.1 innings. Castillo will take another step forward in 2021 and should be a pitcher with an ERA in the low threes and a strikeout rate around 30 percent. I would feel comfortable taking Castillo as my SP4 and in the second round of Fantasy drafts in 2021.

Mick Ciallela (@themick23) – Yu Darvish

Right now, I am leaning towards Yu Darvish as my overall SP4 for 2021. He built on his incredible finish to 2019 and put it together for a full (sort of) season in 2020. He has become a much more polished pitcher since the middle of last season. After having an otherworldly 124:7 K: BB ratio over his final 14 starts of 2019, he followed that up with a 93:14 mark this season. That ratio was good for fifth-best among starters in 2020. In addition to the incredible strides he has made in reducing his walk rate, he has also dramatically increased his GB/FB ratio during the same period. He has settled in as an ace and does not show signs of slowing down anytime soon.

One of the things I like most about Darvish is that he has such a vast arsenal. He can still dominate hitters even when one or two of his pitches is not working. Per Statcast, Darvish was the only pitcher in all of baseball to have a run value of less than -2.0 per 100 pitches on three different offerings. His slider (-3.9), sinker (-2.9), and splitter (-2.2) all reached the threshold, and his cutter (-1.8) and four-seamer (-1.7) were not far off. No other pitcher in the game has as diverse an arsenal. Darvish should continue to be among the very best starting pitchers in baseball once again in 2021.

Corbin Young (@Corbin_Young21) –  Luis Castillo

Difficult question here, and I settled on Luis Castillo with the nasty changeup. He finished the season with 89 strikeouts, a 3.21 ERA, and 1.23 WHIP in 70 innings. When looking at the ERA estimators, his 2.65 FIP, 2.82 xFIP, and 3.04 xERA tell us the ratios could improve. Castillo increased his strikeout rate to 11.44 K/9 and lowered his walk rate to 3.09 BB/9. In terms of K-BB%, Castillo ranked 12th amongst qualified pitchers with a 22.3% K-BB%.

Although we would like him to add a third pitch and hone in the slider, Castillo’s changeup has a career 25.3% swinging-strike rate paired with a 48% whiff rate in 2019 and 40.1% in 2020. His changeup also reached the money pitch threshold coined by Pitcher List in three out of the last four seasons with a 40% O-Swing%, 40% Zone%, and a 15% swinging-strike rate and higher. I expect Castillo to improve with the analytically inclined Castillo has the top-5 starting pitcher upside.

Another notable candidate is Clayton Kershaw. Kershaw finished with a 24.4% K-BB%, a 2.16 ERA, and 0.84 WHIP in 58.1 innings. Although he likely won’t throw 200 innings, the elite ratios with a career 9.74 K/9 provide top-5 SP potential.

Justin Johnson (@JJ_JetFlyin) – Yu Darvish

With the obvious top three of deGrom, Cole, and Bieber, that begs the question as to which pitcher are we most comfortable with following the elite three. For me, it came down to Yu Darvish, Trevor Bauer, Walker Buehler, Luis Castillo, and Lucas Giolito.

For now, I am going with Yu Darvish as the pitcher I am most comfortable with at the head of this tier. Since the beginning of the 2019 season, Darvish was #9 in xFIP, #10 in K-BB%, #17 in K+GB%, #18 in swing strike rate, #19 in WHIP, and #16 in innings pitched (among pitchers who have started 50 innings or more). That is including a rough start to the 2019 season where he really struggled with his command. Since July of 2019, Darvish has been one of the top 3-5 best pitchers in the game and gives me the most comfort in selecting him right I outside of the elite tier.

The regular season just got over but we are already preparing for next year. Keep track of all our 2020-21 MLB Offseason Analysis.

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  1. Zack says

    Hi Fantrax staff,

    I was wondering if you guys could give your input real quick on my SP’s and if I need to add another tier 1-2 starter? This is who I have:

    Chris Sale, Chris Paddack, Tyler Glasnow, Zac Gallen, Sonny Gray, Kyle Hendricks, Corbin Burnes, Tarik Skubal, Michael Pineda and Rich Hill (if he does not retire).

    Thank you guys for all that you do!

    1. Eric Cross says

      In my personal rankings, you have seven of my top-30 or so for SPs. You should be fine there.

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