Sometimes announcers state that a player is not able to catch up to a fastball. Common sense states that the faster the pitch the harder it is to hit. I decided to look at the results of every fastball swung at to see how the results changed as the speed increased or decreased.
Fastballs generally have a 20 MPH difference in speeds (80 MPH to 100 MPH) at the major league level, so a baseline of what happens at every swing needed to be created. I took the results of every fastball over the last 4 years. I divided them up by in 1 MPH intervals (except for those >100 MPH which were grouped together). Then, I divided up the results further into those pitches missed, fouled off, hit into an out or hit for a hit. Taking all the data, I got the following results:
Here is a look at each line:
Miss: The trend is to have more contact until the 89 to 90 MPH range. At this point the swing and miss % increases as the speed gets lower.
Foul: A nice even downward curve from near 50% at >100 MPH to 35% at 80-81 MPH.
Out (in play): At higher speeds, the out rate is at its lowest (20%). It increases to 30% until 89-90 MPH where it steadies out.
Hit: The percentage of hits goes from 10% at >100MPH to 17% at 88-89 MPH. After that point, it slowly declines to 15%.
The main idea to take from this data is the 88 to 90 MPH zone. Above this point, hitters are more likely to miss the pitch and not get a hit. At speeds below this level, the chance for an out (in play) or hit stay the same. Speed, at the major league, seems to help a pitcher for speeds over 90 MPH. Fastball speeds below 88 MPH don’t generally get worse results as the speed gets slower and slower.
To extend this data a bit, here is a look at how hitters with over 350 PAs on the Cardinals and Rangers ranked according to the percentage chance of getting a hit in 2011. I looked at the fastballs over 92 MPH:
Just a few notes on the data.
1. If Albert Pujols is going swing at these faster fastballs, he is going to put the ball in play 50% of the time. Matt Holliday and Nelson Cruz put the ball in play just 25% of the time.
2. Mike Napoli and Daniel Descalso have the greatest problem with making contact on these faster fastballs.
The faster the fastball, the better the result for a pitcher, but the results even out once a fastball goes below 90 MPH. The difference in how batters handle fastball can be seen in the World Series batters. When some announcer states that some hitter can’t caught up with fastballs, you will have a general idea if they are correct or not.
Jeff, one of the authors of the fantasy baseball guide,The Process, writes for RotoGraphs, The Hardball Times, Rotowire, Baseball America, and BaseballHQ. He has been nominated for two SABR Analytics Research Award for Contemporary Analysis and won it in 2013 in tandem with Bill Petti. He has won three FSWA Awards including on for his MASH series. In his first two seasons in Tout Wars, he's won the H2H league and mixed auction league. Follow him on Twitter @jeffwzimmerman.