Aroldis Chapman’s renaissance by the numbers

Aroldis Chapman is having a renaissance season. He was pretty good for most of the year last year, before an awful stretch in August brought his overall numbers down. Last year he finished the season with a 3.22 ERA, 2.56 FIP, and 1.6 WAR. Perfectly serviceable, however, so far this year he has a 1.46 ERA, 1.05 FIP and already 1.3 WAR. Let’s take a closer look as to why that is.

Better fastball results

In 2017, Chapman’s fastball whiff rate (percentage of pitches swung at and missed) was 27.2% according to BaseballSavant.com. This year so far, his fastball whiff rate is up to 35%. That’s a huge improvement. Even when hitters make contact with his fastball, they aren’t doing much with it. Last…