Throwin' Heat

More from The Bill James Handbook 2014. In case you were wondering, no, I'm not a paid advertiser for the book. But I sure like it.

What pitcher do you think threw the most pitches over 100 miles per hour? As with the item about baserunning outs, this isn't a trick question. The answer is Cincinnati's Aroldis Chapman, the Cuban Missile, who threw 282 such fastballs among the 1,099 pitches he threw. Chapman's well known for his fastball. I mean, the guy has a tattoo on his left wrist with that says "105.1 MPH."

But you know who's second? Bruce Rondon.

I'm guessing a lot of you don't know who Bruce Rondon is. He entered spring training as the Tigers' closer but split his time between the Tigers' AAA affiliate in Toledo and Detroit. He appeared in 30 games in each city. 

Anyway, Rondon threw 144 pitches out of 442 that were clocked at over 100 MPH. That's nearly a third of his pitches, compared to a little over a quarter for Chapman. So why did one pitcher close for a playoff team and the other one bounce between AAA and the majors?

It turns out that even if you can throw hard, some pitches are better than others. Chapman was better at getting his first pitch over; he started off batters 0-1 57% of the time, Rondon 41%. Chapman had 6 wild pitches in 63.2 innings, Rondon had 7 in 28.2 innings. Chapman got swinging strikes--complete whiffs, not foul balls--on 16% of fastballs, Rondon on 11%.

Jeff Sullivan at Fangraphs had a great article on the topic of these two. His conclusion is that Chapman gets more strikeouts than Rondon, and is thus more effective, because hitters make more contact against Rondon's fastball than Chapman's, and that's because Chapman pitches higher up in the strike zone, where fastballs tend to get missed or hit in the air, while low fastballs generate more contact and ground balls.

Overall, Rondon had a 3.45 ERA. Chapman's was 2.54. There's an argument that Rondon's failure to nail down the closer's role had as much to do with management's unease at giving the job to a 22 year old as anything else. But for all his heat, his inability to induce swings and misses as well as Chapman kept him from being, well, another Chapman.