Stephen Strasburg threw his slider 17.1% of the time in 2016, compared to 1.4% and 0.5% in 2014 and ‘15, respectively. He didn’t throw one at all between 2010-2013.
He threw it more than his curveball (12.7%), or his changeup (13.1%) last season.
Opposing hitters had a .258 AVG against the pitch, and his ground ball rate was 49.3% with the slider.
He fell in love with it. Strasburg, 28, also thinks it led to the pronator tear that ended his season prematurely.
Strasburg, who signed a 7-year/$175M extension in May 2016, started the season (13-0) with a 2.58 ERA, 33 walks, 138 Ks and a .195/.258/.307 line against in his first 114 2⁄3 innings pitched, then ran into trouble, going (2-4) over his last seven starts and posting a 7.36 ERA, 11 walks, 45 Ks and a .287/.338/.515 line against over his final 33 IP with a DL stint for elbow soreness in August and his final start of the season on September 7th.
He was happy with the results he was getting early, when he was throwing the slider a lot, but eventually things went wrong.
“I was happy with it, but I think my big issue with that — it being a new pitch, it was easy for me to not be able to repeat it and I would get around it and it would get too big and that was the one thing I feel like I was doing in the first half,” Strasburg explained.
“I was throwing it a lot more consistently and just for whatever reason, I don’t know if it was fatigue, or who knows, I’m trying to still figure that out, but I just started coming around it a lot more and not really getting that feel of staying behind it, and it just really aggravated my forearm almost to that point that it led to extra tightness and soreness after starts and then eventually a little tear in the pronator tendon.
“I think the biggest thing with all your pitches is being able to repeat them and throw them correctly and when I was throwing it that much, I think it became easy for me to kind of get lazy with it and maybe fatigue a little bit quicker because it’s just a new stress on your arm that you really have to build up over time. You have to do it the right way. It’s not like any guy can just all of a sudden throw a split-finger fastball and have that be his secondary pitch and have it take place of the two other pitches that are working for you.”
He didn’t however, say that he planned on removing the pitch from the mix.
“I’m not going to eliminate it,” he clarified. “I could have thrown my changeup a lot more earlier in the count, I could have thrown my curveball a lot more earlier in the count. And I think that’s the big learning thing that I had from that.
“Those pitches showed themselves later in the count, when I was ahead with two strikes, but the early contact pitches, for the most part, it trended towards being that cutter/slider and not even my fastball. So I’m just going to continue to fine-tune my changeup and my curveball and use all my pitches at any time in the count instead of just wait to two strikes and show them all, whereas earlier in the count I was just showing fastball/cutter and that’s just — I don’t need to do that just yet.”
Were his catchers in love with the pitch and calling for it? Was he shaking off other pitches to get to it?
“I think it was just I fell in love with it because it was working, especially the first half,” he said.
“It was a quick out. It’s tough when you’re trying to go deep into games and you’re trying to have a pitch that you can rely on that’s not necessarily your four-seamer that they’re sitting on early in the count that you can force them to put the ball in play, minimize your pitch count. I think that’s the thing, when my changeup and curveball are on, their approach has always been, ‘Make him throw it for a strike, I’m not going to swing at it,’ so even if I do execute the pitch, I still have to throw another one to try to get them out. That’s kind of a thing that I really, I guess, can’t worry about too much. I need to still feature it all, because I’m not going to sit here and change my repertoire just for what they’re trying to do and I think that’s kind of what I started to do.”
Nationals’ GM Mike Rizzo told reporters, when asked about Strasburg’s comments, that this wasn’t something that came from the top down, with the Nats identifying it as an issue and telling the right-hander to back off the slider.
“We saw it was a plus pitch,” Rizzo said. “He was a four-pitch mix guy and I thought it elevated him to the elite status that he was at for most of the season.”
Pitchers are always looking for ways to improve. Will it be hard for Strasburg to dial it back when he had so much success with the slider, and stick with what has worked previously?
“I think that you’re always trying to improve your game and it’s tough, because I had success with it,” he said. “I didn’t really think that anything was going on, I just know that based on my symptoms, that pitch just became the one pitch that didn’t really feel good throwing it.
“And with that said, I think a lot of it, looking back on the numbers, a lot of it was just over-use. My arm just wasn’t accustomed to throwing that pitch that many times, because it’s like I was throwing it significantly more even when I didn’t have it.”
“I think the biggest thing from last year is I had a new pitch and I probably abused it,” he said. “I need to go back to what I’ve thrown much longer and not necessarily stop throwing it, but just don’t let it take place of the other pitches that my body has been accustomed to for years.”
His goal going forward, he said, was to figure out how to get through a full season and remain healthy after the frustration of watching his teammates play in the postseason for the second time when he wanted to be able to help.
“I don’t want to miss any more time. I’m not saying that’s not going to happen. There are some times you’re going to get hurt and there’s nothing you can do about it, but I’m going to continue to try to figure out this puzzle and hopefully this next year I’ll have a better grasp on what I need to do to stay healthy.”