2023 Projection Showdown — THE BAT vs Steamer Starting Pitcher K%, Part 2, A Review

Yesterday, I flipped my 2023 projection showdown reviews over to the pitchers, starting with THE BAT’s starting pitcher strikeout rate favorites, compared to Steamer’s forecasts. Now let’s review Steamer’s favorites.

I felt like this was a more interesting group than THE BAT’s, as that system’s favorites were mostly the elite strikeout artists who are rarely going to be undervalued. Once again, Steamer takes the cake here, proving closer on their strikeout rate projections on four of six starting pitchers. Let’s discuss each one.

There was massive disagreement between Kodai Senga’s strikeout rate forecasts. He had posted a career 27.3% mark during his career in Japan, so clearly that 21.8% THE BAT forecasts looked quite pessimistic, even ignoring where he ended up. I don’t know how each system forecasts players coming over from foreign leagues, but I would imagine the methodology must be pretty different seeing how drastic the gap is between the projections. Senga ended up beating every projection out there, as Steamer was most optimistic of them all. He featured a four-seamer that averaged just under 96 MPH and peaked at 100.2 MPH, though the pitch actually generated a below average SwStk%. Instead, it was his splitter that was elite and made him a strikeout machine, as it generated a 26.8% SwStk%. The rest of his pitches, though, were below average in SwStk%, so that makes him risky if his splitter loses any sort of effectiveness.

Another season, another injury for Dustin May. After undergoing Tommy John surgery in May 2021, and returning in late August of 2022, May’s 2023 season ended early in mid-May due to another right arm injury that ultimately required surgery again. He has now thrown a total of 191.2 MLB innings…over parts five seasons. He’s still young enough to think there’s still a chance he contributes in the future, but it’s anyone’s guess what all these injuries and surgeries will do to his underlying skills and performance.

Speaking of injuries, Chris Sale also missed time, recording just 102.2 innings this year. After only throwing 5.2 innings in 2022 due to more ailments, THE BAT projected Sale to post his lowest strikeout rate since 2012. It didn’t happen. Instead, he was right back near his career average. It wasn’t quite peak Sale, but plenty good, and only a lowly 69.9% LOB% pushed his ERA above 4.00. His injury history will continue to make him a risky bet, especially as his game velocity fluctuated severely after returning from shoulder inflammation in mid-August. I’m willing to take the plunge though as his cost is likely to make him a good target.

Nick Martinez only ended up making nine starts, spending more time in the bullpen than the starting rotation. I’m not sure what percentage of his innings as a starter each of the systems was projecting back in early March, but I’m guessing it was more than he ended up with. So those extra relief innings boosted his strikeout rate, as he posted a 21.6% mark as a starter and 23.8% mark as a reliever. Note that his starter mark was still higher than the projections. He bumped his SwStk% up to a career best 12.6%, as he reduced the usage of his four-seamer, in favor of his sinker, changeup and curveball. That changeup was elite, generating a 25.4% SwStk%, so throwing it even more makes sense if it doesn’t take away effectiveness from other pitches.

It was a lost season for Brad Keller, who lost velocity and posted the lowest strikeout rate of his career while he was actually on the mound. He was limited to just 45.1 innings thanks to a shoulder injury, followed by a diagnosis of thoracic outlet syndrome.

It was a roller coaster season for Graham Ashcraft, who was coming off a sparkling spring training in which he posted a 35.2% strikeout rate. Given his high 90s fastball, it certainly increased optimism that this was the first sign of a big breakout. It didn’t happen, nor did his strikeout rate even reach the more optimistic Steamer mark. Essentially a two-pitch guy with a cutter and slider, neither pitch is above average at generating swinging strikes. That would be acceptable if he featured pinpoint control and/or generated a ton of ground balls. But he doesn’t. And his GB% fell below 50%, so he wasn’t all that much above the league average in that department. He may get some sleeper love next year after a 2.81 ERA in the second half, but don’t be fooled — while he did improve his SIERA, it was still an inflated 4.42, and he was fortunate to run a .253 BABIP and high 90% LOB%, both marks that merely brought his season averages back to a normal level.