Cole Hamels Has Been MLB’s Best Starter Since Joining Cubs, Perhaps By Throwing More Fastballs

Cole Hamels has been so good that I cringe when I imagine the state of the Cubs’ pitching staff without him. Honestly, had Hamels not been gracing us with his presence at Wrigley Field, I probably would’ve passed out when word broke about Yu Darvish’s season-ending injury and Mike Montgomery’s shoulder flare-up.

Hamels has compiled a really nice 0.69 ERA over the course of 39 innings in six starts. You can’t scroll any higher on the leaderboards to find a pitcher with better run prevention, and only Zach Wheeler (0.72 ERA) comes close to matching. Hamels’ ERA- of -20 is incredible, too, since it means other the average MLB pitcher has surrendered five times more runs.

That he’s been much better than what his results in Texas showed really shouldn’t come as a surprise when you consider his basket of pitches. We’re talking about a four-seam, sinker, changeup, curveball, and cutter, among which are some of the best secondary pitches you’ll find in MLB. Remember when you read here that Hamels’ three secondary pitches rank in the top 10 of baseball by whiff rate? I certainly recall smiling while researching and writing it.

And what’s even crazier about Hamels’ repertoire is that his best pitch — the changeup — has been even better as a Cub. Batters have whiffed against  roughly 31 percent of his offspeed offering, the highest rate in the game and nearly double the MLB average.

But what’s most interesting to me is how Hamels’ pitch repertoire has changed. Since becoming a Cub, the veteran lefty has thrown far more four-seamers to opponents. Roughly 25 percent of his total pitches were four-seamers prior to being acquired by the Cubs, but he’s steadily increased that frequency to just over 40 percent in August.

While it’s probably not accurate to suggest Hamels’ rise to the top is driven solely by higher four-seam usage, it’s nevertheless an eye-popping change. Maybe the uptick in fastball frequency is helping his changeup play better, too. Or perhaps Hamels’ recent mechanical adjustment is permitting him to throw so many four-seams with comfort, and the rest of his stuff is just coming out better as a result. Who knows?

What we can say for certain is Hamels has been the unquestioned ace of the staff since buttoning up the blue pinstripes. There were more than a few who thought the deadline acquisition was not a big deal. Well, it was a big deal. Adding a pitcher with five filthy pitches is a smart move no matter what a few months of surface statistics tell you.