Gerrit Cole has started the 2018 season with a bang. He currently leads the majors in strikeout rate with 15.43 strikeouts per nine. Coming off the back of two disappointing years with the Pittsburgh Pirates Cole has defied expectations so far. Granted the opposition have been weak. He has faced the Texas Rangers twice (25 strikeouts) and the San Diego Padres once (11 strikeouts). Striking out nearly half the hitters you face is unsustainable but is it possible Cole could become a pitcher who strikeouts at least a batter an innings consistently?
A lot of the conversation following Cole’s move to Houston was that he would have a different pitching coach. Yes that is an obvious statement but it does have relevance. The Pirates are well known for doing it their way and getting success from struggling pitchers but so are the Astros. Maybe the Astros method just suits Cole more than the Pirates method? To better understand these changes we should take a look at the way Cole his utilising his pitching arsenal.
Pitch usage data is from Fangraphs with pitching outcomes from Brooks Baseball.
Fastball and Sinker usage
In the early part of his career (2014-2016) in Pittsburgh Cole threw his fastball around 50 percent of the time. In 2017 that dipped down to 42 percent. So far in 2018, he is back at 48.5 percent and closer to those numbers where he had more success. However, in 2017 Cole gave up 12 HRs on his fastball so why have the Astros got him throwing it more?
Well, the pitch Cole is replacing with the fastball is his sinker. In 2017, the sinker was his second-worst pitch in terms of home run rate (1.15 percent). Over the course of his career Cole has thrown his sinker approximately 17 percent of the time. In 2018 that is now below 5 percent. The strange thing is that Cole was not throwing his sinker much more frequently last season than his career average. So what pitch was he using instead?
The other pitches
Last season Cole replaced his fastball almost entirely with his changeup which increased five percent in its usage. Can you guess which pitch was his worst for home run rate? Yes it was the changeup at 1.18 percent. Accordingly in 2018 he has bought the changeup usage down to approximately 7.5 percent. So if the sinker is down nearly 12 percent, the changeup is down three percent and the fastball is only up six percent what pitches is he throwing instead?
Somewhere we are looking for around nine percent of Coles pitches. These extra pitches have been split fairly evenly between his slider and his curveball. The curveball results have been especially amazing with hitters whiffing 30 percent of the time and only putting the ball in play 3.77 percent of the time. In contrast, the sinker has been put in play 30 percent of the time and the changeup 17 percent.
It will be interesting to see whether Cole can continue his early season success. Whether he does or does not continue his pitch usage is something to keep an eye on. Early in the season, it seems like he has made a concerted effort to move away from his sinker and towards his curveball. With the results of the curveball being so good you would expect he will stick with it.
The other advantage Cole has is that a move to a new league is always good for a pitcher. It is much easier for a pitcher to face new line-ups than for hitters to adjust to pitchers they have not seen before. As the season progresses and Cole sees some of his division rivals three, four or five times we may see hitters catching up to him. The counter to that is that he pitches in a division with some bad teams. The Rangers, Athletics and Mariners could all lose somewhere in the region of 90-games. They also have a ton of hitters who strike out frequently so his numbers this year could easily be the best of his career. Cole has been a ton of fun to watch so far and right now every outing is must watch television.