Stephen Strasburg Returns: A Pitch FX Review
Tonight, Stephen Strasburg returned from Tommy John surgery to make his season debut for the Nationals. Here is a look at his Pitch FX speeds from tonight compared to one of his starts from last season.
| Date | Pitch Type: | FF | FT | CH | CU |
| 08/15/10 | Top | 99.3 | 96.8 | 91.8 | 84.4 |
| Average | 97.6 | 96.6 | 90.2 | 83.0 | |
| 09/06/11 | Top | 98.7 | 97.1 | 91.5 | 82.0 |
| Average | 96.7 | 95.1 | 89.5 | 80.4 |
It can be seen that his average fastball speeds are about 1 MPH slower tonight than last year. The change is nothing to worry about, especially for a pitcher that has a fastball that averages 97 MPH.
The most noticeable change was a “new” off-speed pitch. His changeup was not breaking down as much today. This season, the average horizontal break was -9.4” and the vertical break was 5.3”. Last season the values were -7.7″ for the horizontal break and 0.0″ for the vertical break. Also, the changeup is closer to the same plain as his fastball. This difference can be seen in the following two images (thanks to Brooksbaseball.net):
Note: It can also be seen that his fastballs are not drop as much as they did last season.
2010
2011
The difference in the changeup is due to a different spin axis on the ball has seen from these two graphs.
2010
2011
From the few cut-ins I saw of the game, there was no mention of a new changeup grip. It has a new spin and break compared to the one he threw last season.
Strasburg is throwing a bit slower this season than last. Also, he looks to have added a changeup that breaks down less. As a whole, he seems back in form and the results tonight seemed to speak for themselves.
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 four FSWA Awards including on for his Mining the News series. He's won Tout Wars three times, LABR twice, and got his first NFBC Main Event win in 2021. Follow him on Twitter @jeffwzimmerman.




I saw the game. Good job Ted Lilly for striking out 9.
I didn’t get MLB network at all. They kept going to the rain delay in philly instead of showing the nats game. Is it too hard to put some small wording on the screen that says the other game is in delay?
Yeah, what was up with that. I didn’t even know 9K’s in 5IP was possible for Mr. Lilly.
After the first inning, Lilly had three K’s and Strasburg had 0.
You mean somebody played, even PITCHED, in this game other than Strasburg? I never would have known.
I was at the game and Lilly didn’t look great in spite of the 9 strikeouts. He was getting behind in the count and had a high pitch count. He did work a long at bat against Strasburg before grounding out which is better than his teammates seemed to do at the plate.
Did you see how awful his first swing was? I laughed out loud, then noticed his 0.083 BA.
Strasbury? I don’t get it
Not much to get, I was just seeing if anyone else was awake 😉
The Strasburies taste like Strasburies!
Thanks for the timely writeup on this Strasbury fellow, whoever that is. 🙂 He was probably taking it somewhat easy tonight, possibly on management orders. The new pitch is interesting though. Should that be legal, Stephen Strasburg adding another pitch?
True but he was probably taking it easy last year too.
Hopefully he gets that velocity back as he gets more starts. I think I’m most interested in his curve velocity.
Just watched the highlights, and I am intrigued by that Kemp strikeout in the 4th on the changeup. I guess this article explains it, but man, any other pitcher on the mound and the announced calls that a fastball, no hesitation.
Except for maybe Felix Hernandez who throws his change in the low 90’s.
I know pitch type linear weights aren’t GREAT, but I find this odd: his fastball (avg ~93), has been a negative pitch in terms of value. His changeup, which is 3 to 4 MPH slower (not ideal according to conventional wisdom), has been a fantastic pitch. You’d think that such a small difference in velocity would make the changeup worse, not better.
Please send me one “AF tank woman.” My check for $17 is in the mail.
Hmmm, now that the spam post has been deleted my witty riposte makes considerably less sense.
I will gladly pay you tomorrow for a hamburger today…
I was more impressed with 56 pitches through 5 IP.
Small sample for certain.
Last year SS had TWO changeups: [1] One that he threw to LHBs that tailed away, and [2] One that he threw to RHBs that dropped.
The number of LHBs and RHBs in the LAD lineup compared to what he faced on average last year could account for the differences in changeup movement, couldn’t it?
This dude is either going to be [1] AWESOME!!! or [2] injured. He’s not going to be one of those “reduced stuff” pitchers, and probably never will be.
I did not notice anything different in his mechanics, which could be a future issue.
His plant is different on the centerline.
FP Santangelo claimed that Strasburg had added a 2-seamer to his repertoire that was 94-96 mph. I saw it all of twice, so if he did it’s a supplemental pitch and not one of his main pitches.
If he did, that’s 4-6 MPH faster than the other 2 seam FB in the league. I would expect him to add a cutter like Nalasco throws that avoids the slider torque on the arm as well.
Yeah, Strasburg does throw a two-seamer. Thing is, he threw one last year, too. And in college.
No idea why Santangelo thought it was a new pitch.
Because he barely uses it, and when he does we (fans) don’t notice because we’re conditioned to think that 96 HAS to be a 4-seamer. So much so that I’d forgotten about it.
How does the pitch data from this year’s only start compare to the individual starts from last year?
Are there any games that are almost identical to this one (in terms of pitch fx data)?
We’re comparing 5 IP from one start to a single start from last year. That seems like something FG should never do.
Your right, I think it’s a difference without a distinction. 99 MPH – 100 MPH, it’s the differential to the changeup, not the overall velocity that drives his game. That delta tells the tale.
same “plane”, not plain