How Félix Hernández got his groove back

Since August Félix Hernández has been on a tear. Pitcher wins don’t matter but they still make us happy and since his August 5 start against the Angels he’s gone 4-1; ERA isn’t indicative of pitching ability but seeing that number drop below 3 still feels pretty good. We are, of course, still talking small sample sizes, but even taking into account his first three starts off the DL he’s shown major improvements. If you wanted to *gasp* create a more humanist narrative about the starts since he’s returned you could make the argument that being on the DL for that length of time subsequently requires a certain amount of time to get back in the groove. But, as has been vocalized by a loud contingent of this community, narratives are Bad and obscure the facts, so I will silence my inner Aesop and stick to the numbers. Specifically, this piece will focus on his August starts because they’ve shown the most dramatic improvements thus far.

For reference, here is the Fangraphs chart for these five games.

His walk rate is still up, worryingly so in the Tigers and Angels games especially, and this line preys on arguably our greatest fear for Félix: that he’s lost his command. There is, however, an interesting correlation between the higher BB/9 of those games and the higher K/9, which could be indicative of a recent refrain that Félix has had trouble getting hitters to chase out of the zone pitches. We see this more so in his first start against the Angels.

The majority of Félix's strikezone plots feature pitches outside the zone, but on August 5 he was missing more obviously, which led to hitters swinging at just 28.3% of pitches out of the zone. His command seems to stabilize beyond this point though, with pitches scattered more enticingly around the zone and fewer "Ball In Dirt" plot points.

These strikezone plots also highlight what I believe to be a major source of Félix's renewed success: keeping the ball in the lower half of the zone. It’s no secret that the mid to upper part of the strikezone is a dangerous place for pitchers, but by throwing the ball lower, and subsequently missing lower, Félix can more easily mitigate the likelihood of giving up homeruns and hard contact, though the Hard% has vacillated somewhat irregularly in these five starts with a low of 14.3% and a high of 45.5% (inexplicably against the Milwaukee offense). This is as good a time as any to point out how little we understand about the correlation between contact quality and positive outcomes.

The other element to consider when looking at the King’s renewed rise is pitch usage. Since returning from the DL the use of his changeup, fastball and curve have all increased, while there has been a sharp decline in the use of his sinker. When it comes to generating whiffs the change continues to be his most effect, though a recent increase in the use of his curve has proven effective as well. Additionally, although it’s an incredibly small sample size, hitters have had a lot of trouble making contact with his cutter, in the few times that he has thrown it.

Lastly, for all the talk of his declining velocity, Félix has actually generated a growing number of whiffs from his fastball, which likely has positive connotations for his command and pitch location. This can be seen in the Brooks Baseball graph below.

Bottom line, although this is no longer the 10 Ks, no walks, streak of extra high quality starts Félix whom we’ve worshipped for years, he is still a remarkably effective pitcher. A growing ability to keep his pitches located further down in the strike zone, coupled with greater fastball command have helped contribute to a successful recent run. Hopefully these last five starts, in particular, demonstrate a step forward for the King because goodness knows we’ll need him at the top of his game for this final stretch.