I think this graph, courtesy of Fangraphs sums up Kevin Gausman’s season so far. It would make a decent rollercoaster.
You can see that his rolling average ERA didn’t drop below 5 until very recently. He has spent most of the season hanging out in the 6+ range. What was most surprising about his horrible, no good start to 2017 was that he was better than ever in 2016. Unless you count his 2013 season when he was mostly used as a reliever, he set career bests in K%, K%-BB%, BB%, and xFIP. That seemed like an excellent foundation to build on coming into this season.
However, by now you’ve probably realized that the most recent portion of that ERA graph portends good news. Maybe he’s fixed! Maybe everything is better now! Let’s find out together.
I’m going to start by splitting up his 2017 stats into two chunks. Obviously, I didn’t choose these at random. I’m comparing good Kevin Gausman and bad Kevin Gausman.
The transformation is dramatic. In every way, he’s been a better pitcher. More strikeouts, fewer walks, more grounders, more swinging strikes, you name it. Yes, his BABIP was very high early on, but it’s still high so we can’t blame that for all his poor results early on. His recent stretch of good play isn’t due to fewer home runs on fly balls, so we can rule that out.
Ok, so he’s been ace-like for over a month now. Is it sustainable? What happened here?
Maybe he started inducing weaker contact. It’s a perfectly reasonable explanation for improved performance (at least in terms of ERA, but not Ks and BBs).
Yeah, I’m surprised too. He’s actually allowing more hard contact now that he’s pitching well. That was not expected. In spite of all of this increased hard contact, he’s been excellent. That was a dud, let’s look at something else.
I was going to suggest looking at ground ball rate, but I’ll save you the graph and just say it doesn’t show much at all. It’s pretty flat for the most part, so there’s nothing there.
Maybe his improved strikeouts are due to getting hitters to chase out of the zone more?
Yep, looks like it. That is steady improvement all season long, peaking right now. That will certainly increase strikeout rate. Again, I’ll save you the graph, but his zone swing % shows roughly the same trend. That means hitters are simply swinging at more of his pitches overall as the season goes on. That’s good because of this:
It’s not as long a trend as the others, but there is a sharp increase in his most recent starts. More swings = more swings and misses when you have a swinging strike rate graph like that one.
What else is contributing? Well, let’s look at how well he gets ahead in the count:
Look at that, another stat trending up all season. He didn’t cross league average until a few weeks ago. Getting ahead in the count with a first pitch strike certainly helps with both K% and BB%. FYI, his rate of pitches thrown in the zone hasn’t really changed much over the season, so the increase in strikes is mostly swinging strikes. That’s good because it is more in Kevin’s control.
What Did He Change?
Ok, ok, I know what you are thinking at this point. That’s all great, but it just answers the what not the how he got better. What did he change? I’m glad you asked.
These are three of his most used pitches. I left out his four seam fastball (his most used) because it screwed up the scale on the graph, mostly. It shows a small dip in games 15+, but is basically flat all season. Gausman appears to have significantly reduced the usage of his slider in favor of both a sinker and his excellent splitter. His splitter and sinker use increases coincide very well with upticks in all his other stats.
His splitter has consistently gotten the most swings and misses of all his pitches, so using it more is obviously good. For some reason, his other pitches have also benefited from more sliders and sinkers, with all of his pitches showing increased whiffs. All of these improvements have taken him from awful against both RHB and LHB to just awful against lefties.
No pitcher should be allowing an average over 0.300 against RHB if they want to last long as a starter. The dramatic improvement against righties has been instrumental in his comeback. Lefties are swinging and missing as much as righties against him in this most recent run of success, though.
I would say that Gausman’s improvements are sustainable as long as he continues to throw his splitter and two seam more and his slider and four seam less. This change has clearly worked and I see no reason for his success to end if he keeps it up. In fact, he’s still carrying an unlucky HR/FB% and BABIP during this great run on top of a very high Hard% that could come down. There are lots of signs pointing to continuing success. The terrible Gausman of April and May is gone. It’s time to pick him up in most leagues, if he’s still available. Tschus!