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Wellemeyer’s Velocity

This afternoon, we looked at Johan Santana‘s loss of velocity of late, and what it might mean for him going forward. Let’s pull a double header and take a look at another National League arm who has recently wondered where his fastball has gone – Todd Wellemeyer.

In a conversation after his last start, Wellemeyer told the St. Louis Post Dispatch “Last year I was throwing 94-96 (mph), this year I’m topping out at 90-91. I don’t know what it is but there’s definitely a difference. It makes things more of a challenge, that’s for sure.”

A 5 MPH decrease in fastball velocity would be a huge red flag, and something that very few pitchers could actually overcome. Thankfully, Wellemeyer hasn’t actually lost that much zip on his fastball. Here’s his Pitch F/x velocity chart.

As you can see, his fastball averaged 92-93 for most of last year, and there certainly were games where he was throwing 95 to 96 at the high end. This year, none of his top end speeds reach 95, and in three of his last four starts, the average fastball has come in around 90-91. So, while he hasn’t lost 5 MPH off his fastball, his average speed is down from 92.7 a year ago to 91.3 this year.

Unlike with Santana, who is still topping out at the same speed as always, Wellemeyer’s top end fastball is down significantly. He’s thrown 7 pitches at 94+ this year, the fastest of which was 94.4 MPH. For comparison, he threw 36 pitches at 94+ in one game last year (July 6th against the Cubs), the fastest of which was 96.1 MPH. 28 of those 36 pitches were faster than any pitch he’s thrown this year.

Why has his top end fastball gone away? Well, if he doesn’t know, and Dave Duncan doesn’t know, odds are pretty good that I don’t know either. But, unlike with Santana, I’d suggest this is certainly a legitimate cause for concern long term. A sharp, significant decrease in top end fastball velocity is fairly highly correlated with arm injuries. Not always, of course, but it’s pretty common that a guys fastball disappears and he ends up on the disabled list in the not too distant future.

I told Mets fan not to worry about Santana. Unfortunately for St. Louis fans, I’m not sure I can say the same thing here. It’s probably time to worry.