Pitchers Who Were Hitting Their Stride

With only a two month season, it makes sense to look into pitchers who were gaining momentum in the final month. Of course, taking a small sample isn’t always ideal but perhaps a pitcher started to gain velocity, made a pitch mix change, or were just plain unlucky in the first month. These tangible changes could mean something and could hint at who will carry their success over into 2021.

Here are the top 30 ERA leaders in the last month:

Some typical names like Bauer, Cole, and Bieber can be seen towards the top. We are going to take a look at some of the more interesting names to see if we can find anything to justify their numbers. 

Walker enjoyed a nice season with an overall ERA of 2.70. In fact, Walker’s ERA improved month by month this season. His ERA’s per month were 4.35 (10.1 IP in July), 2.78, and 1.77. A lot of luck seems to be involved here because those ERA’s are matched with a 3.87, 5.04, and 4.37 FIP. 

What he did that is somewhat intriguing is he ditched his sinker. His sinker has below-average movement and hitters had an astonishing 173 wRC+ against this pitch. On the other end, he increased his four-seam fastball usage to replace the sinker. Overall for the entire season his four-seam was his best pitch in terms of pVAL making this a smart move. 

So we have a pitch mix change which means maybe Walker figured something out right? Not so fast. That four-seam fastball he started to throw more comes with a .167 BABIP (career average .280) on the season. As if BABIP luck wasn’t enough, the expected stats call for regression as well. In the month of September his fastball had a wOBAcon of .185. Throughout his career his fastball has averaged a wOBAcon around .285.

While the pitch mix is welcoming, the four-seam clearly overperformed in September. Pair that with the subpar FIP’s and Walker seems to have had a lucky month in September. For 2021 Walker is likely just a back end of the rotation type of guy or perhaps just a streamer.

One of the more impressive rookie campaigns this year belongs to Ian Anderson. With so much hype around Sixto Sanchez, it seems as though Anderson hasn’t been getting much of the spotlight. In 2020 he started six games producing a 29.7 K% with a 1.95 ERA and 2.54 FIP.

As you know here at Fangraphs we don’t rely on surface-level stats. The first problem here is that 29.7% strikeout rate. It comes with an average 11.9 SwStr% which means the strikeout rate should come down as these statistics are correlated. The main worry here is his arsenal. The first issue is his changeup and fastball only have a small velocity difference between the two.

They don’t compliment each other in terms of keeping hitters off-balance. Another issue is he is missing a pitch that causes hitters to chase outside of the zone. The highest chase rate on any of his pitches is 30.6%. Lastly, if you look at the movement on his breaking balls none of them have a ton of break. They move in very subtly and lack that wow factor.

Although the strikeout rate should come down Anderson does undoubtedly create weak contact. In 2020 he was top 10% in Barrel%, xBA, wOBA, and wOBAcon. The weak contact will likely stay but with minimal strikeout upside and an arsenal that has some red flags he should only be a late-round flier coming into next year.

Want to know who had the lowest FIP in the month of September? Joe Musgrove. In the last month of baseball Musgrove had a 2.16 ERA, .198 batting average against, and a 1.39 FIP. He also had an elite strikeout rate and elite walk rate. Overall a great month but again this is a small sample so what the heck do we do with it?

Well coming into 2020 what did we want from Joe Musgrove? We wanted him to throw the fastball less and his breaking pitches more. He did exactly that. His fastball went down about 9% in usage compared to last year. In return he upped his slider and curveball, both of which had a positive pVAL and above-average whiff rate. I know it sounds like a broken record at this point and people are tired of hearing it but Musgrove is someone to grab for 2021. 

After the month of August, Kevin Gausman seemed like a prime candidate to break out in the final month. In August Gausman put up an average ERA of 4.28 but was very intriguing due to his K-BB% of 27.0%. Those who invested reaped the benefits of his 2.25 ERA in September. The best part about Gausman in September were the strikeouts, providing two starts where he put up nine. 

So what isn’t there to like? Well, Gausman essentially relies on one great pitch which is his splitter. Splitters can come and go which is an issue. Plus we all know relying on one pitch isn’t what we look for in a pitcher. That being said he clearly can go on some nice runs and we can expect a high three ERA with high strikeout upside for 2021. 

John Means had a great rookie season in 2019 and popped up on a lot of sleeper lists coming into 2020. That was quickly forgotten because in the first two months Means produced an 8.59 ERA and 8.03 FIP. The main issue was Means’ fastball as he had trouble commanding it leaving it over the heart of the plate way too often.   

That all turned around in the final month of the regular season. He finished September with a 2.48 ERA and 4.36 FIP. Most notable was the difference in his strikeout rate. Means bounced up from a 17.0 K% to 27.9 K%. The big difference is without a doubt because of his fastball. Check out the differences in his fastball from August to September.

Means dropped the velocity and had better command placing it on the top of the zone on a consistent basis. With that came a much higher SwStr% and he was finally able to set up that lethal changeup of his. 

Means is someone to watch in 2021 spring training. Carefully watch his fastball velocity and if he is commanding it at the top of the zone. If he is, he is well worth a late-round flier.