Reviewing the Rotation, part IV: Drew Hutchison

What a difference a couple weeks makes. Had I started this series with Drew Hutchison about three starts ago, this would have read quite differently. I was very optimistic about Hutchison coming into 2015 after noticing how good his slider was down the stretch last year which drove significantly better results, especially in terms of strikeouts.

Unfortunately, after six starts, Hutchison was barely averaging five innings per start, and his results had gone backwards across the board. Not only did he not seem to feel the feel for his slider, but his fastball command was spotty at best. Though his 7.47 ERA overstated exactly how poorly he was pitching (5.16 FIP, 4.73 xFIP), it was a major blow to an already beleaguered rotation. Happily, he's since turned things around in his last four starts, capped off by his brilliant outing this past week against the White Sox. The way he dominated using fastball command without being sheerly overpowering was a flashback to last May when he outduelled Yu Darvish and the Rangers in a similarly economical manner.

So what to expect for the rest of the year? We'll start with the usual headline numbers, as well as some relevant splits from both seasons:

In 2015 compared to 2014, Hutchison's strikeout rate is down 3% (about 1 K/9) and his walk rate down 1%, and his BABIP up 19 points. The biggest difference though is that his ground ball rate is up almost 10%, a significant change. Even giving up slightly more home runs per fly ball, that has pushed his overall home run rate down by about 17%, from 1.1 HR/9 to 0.9 HR/9. What's particularly surprising is that he's done this despite using his four seam fastball a lot more (59% vs. 49% in 2014), mostly at the expense of his two-seamer (9% vs. 16%). However, his ground ball rates on his two seamer and change-up have spiked way up: from 38-39% last year to 76% and 61%respectively. This causes me to be skeptical that the higher rate will continue, but even if some of it were maintained that would be a huge plus in terms of limiting damage on long balls.

The big difference in Hutchison's season is also evident in the data -- strikeout rate up from 16% to 27%, walk rate down to 4% from above 8%, BABIP down to his 2014 average, and home runs completely drying up. These are inherently small samples, so a lot of things will end up somewhat in the middle (Hutchison won't walk only 4% of batters, and won't have fly balls leave the park as often as 13.5% or as little as 5.6%). The BABIP difference makes sense considering the difference in command, as Hutchison was getting squared up a lot in the early going.

Hutchison's strikeout rate was way down in those first six games at 16%, and has spiked to just under 27% his last four starts, roughly the same rate he had from July to September last year. However, it still trails the ridiculous 33.5% he posted down the stretch last year (not that one would expect that to be matched). Anecdotally, I've thought his slider has been sharper the last couple starts compared to the early going when it flatter and frequently hanging, but it's not back to where it was last year:

While he's got getting the great vertical finish he did last last year, he seems to have found consistency, and that's probably the most important thing going forward.

One of the most important things Hutchison has done to turn around his season is resume dominating hitters when he has them on the ropes. In 2014, when Hutchison got into dominant pitcher counts (0-2, 1-2), he was terrific, allowing a contact rate of just 67% (league: 74%) which allowed him to pile up strikeouts. And when batters did put the ball in play, they did very poorly: they hit about .230 compared to league average around .290 in those situations, with almost no power (40 points of ISO compared to league average around 75 points). Heads, Hutch won; tails, the batter lost.

In Hutchison's first six starts however, batters made contact 79% of the time in dominant pitcher counts, so he wasn't able to finish them when ahead. And that contact hurt him. While I can't split out the season data, in 2015 his BABIP on 0-2 and 1-2 pitches is about .350, and my guess is that would be even higher for those first six starts. His ISO is still in line, so this means a bunch of singles were falling in. While it's tempting to just say "bad BABIP luck", this was really about not having a consistent quality slider and poor fastball command. Pitches stayed in the zone, and hitters were able to put quality swings. In his last four starts, when his command and slider have been better, the contact rate is down to 71%, and combined with doing a bit better of a job getting ahead, the strikeouts are way up. IN the end, baseball is pretty simple: get ahead, and put batters away when you have the chance.

Another interesting point is Hutchison's platoon splits. Since he relies on a four seam fastball so much and his best secondary pitch is a slider, lefties can be expected to hit Hutchison better than righties. And this is what happened last year, as lefties hit .256/.334/.477 with about a 2:1 K:BB compared to righties at .222/.272/.343 with a 5:1 K:BB. This year however, things are reversed, with lefties hitting .231/.285/.364 and righties hitting .302/.368/.458. More compellingly, the strikeouts and walks have evened out.

I mentioned above that Hutchison has cut way back on his two seamer, and it turns out it's almost totally against lefties: last year he threw 20% two seamers, this year only 7%. This is counter intuitive, because two seamers have arm side run for the pitcher and tail away from opposite handed batters, which should help keep the ball away from the danger zone over the plate whereas four seamers don't have the same horizontal movement. But it may be the case that better execution of his four seamer makes it a more effective option to lefties. Again, expect regression here too (positive against righties, negative against lefties), but it's worth keeping an eye on, and hopefully Hutchison can continue to better contain opposite handed hitters.

Bottom line: Hutchison struggled badly the first month of the year and his velocity was down a tick. His command was inconsistent, frequently poor and he wasn't finishing batters off. The last couple weeks, the velocity is back up a little, the command is back,  and his slider is better if not as good last at the end of last year. This should allow Hutch to be a solid, middle of the rotation starter. And keep an eye on his ground ball rate and numbers against lefties to see if his 2015 improvements continue.