Dr. Dallas and Mr. Keuchel — The Two Faces of the Astros Ace

Plenty of aces fell off of cliffs in 2016. There was Adam Wainwright, who looked to be moving towards inevitable age-related decline. There was Zack Greinke, who crashed and burned after signing a huge contract. And then there was Dallas Keuchel — the 2015 AL Cy Young Winner.

Keuchel himself said that he “sucked” in 2016. It’s easy to underscore how badly he fell — his ERA and FIP both skyrocketed, his HR/9 almost doubled, and he saw his walks go up plenty. Keuchel admitted that he had pitched through shoulder pain in much of 2016, which may be partially to blame for his struggles, but I’m not 100% ready to jump on board the “Dallas Keuchel will bounce back in 2017” train just yet.

One of the biggest things that jumps out at me was that Keuchel himself wasn’t actually particularly unlucky in 2016. Both his LOB% and BABIP were very close to the league averages of 70% and .300, respectively. His Cy Young season saw both those figures deviate significantly from the league averages and career averages to Keuchel’s benefit. Perhaps his 2015 season wasn’t truly Keuchel’s real form.

Keuchel, as a groundball pitcher, needs a good defense behind him. After all, Kyle Hendricks, who profiles as a similar groundball pitcher, had the leagues’ best defense behind him when he won the 2016 ERA title. Maybe the Astros lost some defensive prowess from 2015 to 2016?

Unfortunately for Keuchel, the opposite was the case — the Astros went from a -7.6 DEF rating in 2015 to +11.2 in 2016. Keuchel should have been even better in 2016, but he got worse, way worse.

Part of this was difficulty inducing ground balls and weak contact from hitters. Keuchel saw his GB% decrease by 5%, and his FB% rise by an equivalent amount from 2015 to 2016. He also saw his Soft% and Med% decrease, while his Hard% rose by almost 9% over the same stretch. He just wasn’t effective.

Some of this can be contributed to his arm troubles, leading to velocity loss and getting hit even harder. But the real issue with Keuchel was his placement.

These heatmaps show his Swing% from 2015 to 2016 (left to right). Keuchel gets far fewer batters to chase out of the zone pitchers (O-Swing% went from 33.3% to 30.1%), which was how he got his strikeouts in 2015. From 2015 to 2016, he saw his K/9 drop from 8.38 to 7.71 — and his walks went up from a 1.98 BB/9 to 2.57 BB/9. While Keuchel certainly isn’t a strikeout pitcher, that’s not to say that Ks don’t help.

But this really can’t be attributed to the arm injury, or velocity — it’s that Keuchel wasn’t fooling hitters in 2016 as he did in 2015. He was also throwing more pitches in the zone (Zone% increase from 37.6% to 41.6% from 2015 to 2016). His Z-Contact% stayed almost the same, but batters’ contact increased simply because he threw it in the zone more frequently, possibly to counter the fact that he wasn’t getting swings out of the zone. Batters have simply figured Keuchel out, and he’ll need to change up his tricks if he wants to succeed in 2017.

So, we have two extremes now for Keuchel. We have Dallas “Everything’s going right for me” Keuchel, whom we saw in 2015, and we have Dallas “This is what happens when I have league average luck” Keuchel, whom we saw in 2016. Unless Keuchel starts relying on voodoo BABIP magic, I doubt we’ll see the 2015 version reappear.