We don’t need statistics to tell us that Mo’s cutter is one of the best pitches, if not the best pitch, in baseball history. Hitters know it’s coming. It consistently sits 92-94 mph, so they can time it. Yet they cannot make good contact. It has been this way for well over a decade now, and Mo willing it will continue for at least two more years.
The craziest part about Mo and his cutter is that it has seemingly gotten better with age. He might not have broken any saves records last year, but Mo posted one of the most dominant seasons of his career, registering a 0.67 WHIP and walking only six hitters in 70.2 innings. How does he do it? Thankfully, we have pitchf/x to help us answer, and iamawesomer at Beyond the Boxscore takes a look at the data.
I could probably just quote the entire article, because it’s pretty mind-blowing. The most important point I took from it is that we really shouldn’t refer to the pitch as “the cutter.” Rather, it should be “a cutter,” since he throws it with varying degrees of spin. This ranges mostly between 150 and 200 degrees, so he’s mixing up the pitches even though he’s not mixing up the pitches.
Mo overall threw the cutter 82 percent of the time, with the rest being four-seam fastballs. Yet against lefties he throws the cutter almost exclusively. Not only that, but his pitches to lefties tend to concentrate in one area: high and tight. This is even more amazing because of the speeds of his pitches:
Doesn’t need to mix it up speed wise, with the vast majority of both the cutter and fastball clocking in between 92 and 94 mph. By some quick rough calculations it comes out to about a hundredth of a second difference in time to reach home plate (.435 seconds for 92 mph and .446 for 94 mph.) The fact that hitters can more or less time themselves to within a hundredth of a second of when to swing and still can’t do anything about Rivera’s pitches speaks volumes of them.
You know what lefties hit against Mo last year? .147/.173/.194. So let’s get this straight. Lefties know the pitch type, speed, and location before they even step into the batter’s box, yet they can’t even come close to replacement level production. There’s a reason why we say praise be to Mo.
To close things out, here’s an animation of Mo against the Padres last year. Those chumps didn’t stand a chance. I could seriously watch this video all day long. (As to not slow down the main page you’ll have to click on read more to see it.)