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Being patient with Stephen Strasburg's rehab should help Washington Nationals in second half

Today we're going to take a look at what to expect when Stephen Strasburg returns to the Nats roster with an assist from Greg Young of The Nats Blog.

Will Stephen Strasburg rebound when he returns from the disabled list?
Will Stephen Strasburg rebound when he returns from the disabled list?
David Kohl-USA TODAY Sports

[ed. note - "This article is one half of a point/counterpoint argument with Greg Young from out friends at The Nats Blog. Check out the other side of the debate HERE or through the link included at the end of this story."]

Before Stephen Strasburg was finally placed on the disabled list on May 30, we heard a laundry list of possible explanations for his struggles.  Strasburg dealt with an ankle injury in Spring Training that made him alter his mechanics.  This apparently caused some shoulder pain that led Strasburg to have a chiropractic adjustment.  Next, we heard that Strasburg had a strained lat muscle.  Finally, he left his start on May 29 after one inning with neck pain and hit the disabled list.

If you think about it, that's a whole lot of swinging and missing by the Nats training staff as they tried to diagnose what was bothering Strasburg. Over a five start span, they came up with three different (new) injuries and determined that they may have been caused by a mechanical adjustment that he made back in March.  When Strasburg was placed on the disabled list, the word I uttered wasn't an expletive.... It was "Finally!"

Fangraphs Jeff Sullivan took a close look at Strasburg a few weeks ago.  At the end, he surmised that Strasburg's problems may stem more from remembering his injury in March (leading to the mechanical adjustment) than any current injury.  Almost a month later, I tend to agree.

Whatever it really is that's kept Strasburg from performing at the level we've come to expect, it's something that the Nats weren't having an easy time correcting with a bullpen session or two between starts.  Even two weeks off and quite a few bullpen sessions are unlikely to fix the problem.  Let's check out the quote from Steve McCatty that Sullivan referenced in the article above....

"We worked on it and he was right on line in the bullpen," McCatty said. "He had great alignment throwing in the bullpen the other day, and his stuff was great. [Tuesday] warming up in the bullpen, I just walked out of there saying, ‘Wow! Wow!’ But then you go out there, get two quick outs and sometimes when you struggle, you wait for the other shoe to fall."

Bullpen sessions are great and all, but facing live hitters is a completely different story.  Throwing a bullpen session, a pitcher doesn't really have to adjust to anyone in the batter's box.  He never has to work from the stretch and keep a close eye on a runner at first base.  He can just go out there, relax, and think about the target.  Perhaps throwing a simulated game could be more helpful with some of the noise factors, but it's still not the same as throwing in a real game.


The Strasversity hashtag that we often see posted on social media is a mocking gesture towards the segment of the Nats fanbase that questions his mental toughness.  Of course, when people do question Strasburg's mental toughness, it's all just speculative nonsense.

  • Strasburg built himself up from being an overweight high school pitcher who threw 91 MPH that nobody wanted to becoming the most sure-fire number one pick in the history of the MLB draft (at the time, of course).
  • He justified the pick right away, reaching the majors after just eleven minor league starts and posting a 2.91 ERA as a rookie.
  • His 3.25 ERA since reaching the majors in 2010 is 24th in baseball over that span.  He's certainly performed well at the highest level, which is difficult to do in any profession.
  • He battled back from Tommy John surgery to post a top 20 ERA and the second best FIP in baseball in 2012.  Having a torn UCL is a physical injury, but it certainly does take some mental toughness to be able to jump back on the mound and trust your stuff right away.

Any time people talk about how Strasburg is mentally weak, I wait to see if they can offer some kind of proof other than anecdotes such as, "Someone made an error behind him and he imploded."  Alas, I've gotten off topic a bit.....

There's a reason I'm titling an entire section of this post "Strasversity."  We usually see Strasversity brought up on social media because there's been an error behind Strasburg (or another Nats pitcher).  I'm not going to look solely at errors, though... Let's have a look at Strasburg's splits with the bases empty and runners on base.  We'll throw in runners in scoring position for good measure.

Here are Strasburg's career splits...

Bases Empty .215 .270 .337 .271 1760 352 37 108 527
Men on Base .256 .319 .391 .312 1071 253 28 72 264
Men In Scoring .254 .321 .381 .305 609 142 13 48 147

Let's start by stating the obvious.  I've brought this up in regards to Strasburg before, but we shouldn't be surprised that he doesn't perform as well with runners on base.  Very few pitchers do.  When runners are on base, they pitch from the stretch rather than the windup so that they can hold runners close.  This almost always costs pitchers something. For most, they lose a tick off their fastball.  For some, they just don't maintain the same break with their off-speed pitches as they do from the windup.  Many struggle with command pitching out of the stretch as well.  If pitchers felt as comfortable or were as effective pitching from the stretch as they did throwing from the full windup, they would probably never use a full windup.

Over the course of his career, Strasburg has been phenomenal with the bases empty and slightly better than league average (.251/.332/.405 from 2010-2014) with runners on base.  Of course, his performance with runners on base relative to pitching with the bases empty is a bit different.  From 2010-2014, the league average wOBA allowed with the bases empty was .311.  With runners on, it was .320 (+.009).  Strasburg has allowed a .312 wOBA with runners on as opposed to .271 with the bases empty, which is a much more significant 41 point difference.  Pitching with runners on base has always been a bit of a problem for Strasburg relative to the rest of the league.  2015 has been extreme, though....

Bases Empty .259 .314 .455 .334 121 29 4 9 33
Men on Base .398 .457 .553 .439 96 35 2 5 12
Men In Scoring .387 .419 .593 .435 64 24 2 1 9

Let's start by noting that Strasburg hasn't been nearly as good with the bases empty as he has been in the past few years.  His struggles don't all relate to his performance pitching out of the stretch.  From 2010-2014, Strasburg was one of the best starters in baseball with the bases empty.  This year he's been below league average (.245/.302/.388).

With runners on, Strasburg has been a gas can.  He's allowed a .439 wOBA.  There are just three players in the league with a wOBA better than .439 so far this season: Bryce Harper, Paul Goldschmidt, and Anthony Rizzo.  So far in 2015, if Stephen Strasburg is facing a batter with a runner on base, he's basically turned that hitter into Anthony Rizzo (.440 wOBA).

Yes... The premise of Strasversity really existing is comical.  However, the concerns with Strasburg's performance when runners are on base seem valid.  The Nats might be best served giving him an opportunity to work in more live game situations where he can work on his mechanics from the stretch to see if he can sort them out.  That's not the whole problem, but it's been a significant part of it.


When you see a pitcher struggling as badly as Strasburg has, there are usually two main things that immediately spring to mind as the source of his problems.

  1. He could be dealing with diminished velocity/movement on his pitches.
  2. He could be struggling with command

While "fixing" a pitcher with command issues isn't easy, one of these problems is a lot more fixable than the other.  If his velocity and movement are down, a pitching coach can try to work with him on tweaking his mechanics to find that extra tick on his fastball or get his curveball to spin and sink a little more.  Ultimately, all pitchers see their stuff diminish throughout their careers, though.

Command is something that seems more possible for a pitching coach to fix.  A minor tweak in a pitcher's mechanics could help him hit his spots a little better.  Working with a pitcher on changing his arm slot could help improve a pitcher's command.  Heck... Even changing where the pitcher is standing on the rubber can help mask command issues a bit.  While a pitcher's command also has quite a bit to do with their physical tools, it's far more likely that coaching can help correct command issues than issues with a pitcher's stuff.

Strasburg's stuff hasn't been nearly as much of an issue as his command has thus far in 2015.  Let's start out with velocity.....

Month Fourseam Sinker Change Slider Curve
3/14 93.99 93.38 87.62 86.73 78.57
4/14 95.56 95.39 89.29 87.41 79.77
5/14 95.57 94.11 88.67 0 80.47
6/14 95.34 94.56 88.8 0 80.11
7/14 95.8 95.53 88.86 0 80.82
8/14 95.66 95.19 88.95 0 81.26
9/14 96.19 95.72 89.49 0 81.9
10/14 96.26 96.08 89.61 0 82.69
4/15 95.24 93.66 88.12 91.08 80.93
5/15 96.62 96.5 89.71 90.72 82.56

H/T to Brooks Baseball

His velocity is pretty much right where it was last season on all of his pitches.  Velocity doesn't seem to be a problem, in other words.....

How about vertical movement?

Month Fourseam Sinker Change Slider Curve
3/14 10.55 7.47 3.81 0.76 -9.73
4/14 8.87 5.87 3.41 0.39 -8.51
5/14 8.58 6.53 2.92 0 -7.49
6/14 8.73 6.26 3.36 0 -7.31
7/14 8.43 5.17 3.17 0 -7.02
8/14 9.46 6.41 3.77 0 -6.71
9/14 8.9 5.94 3.48 0 -6.27
10/14 7.89 6.67 2.5 0 -5.62
4/15 9.2 5.48 3.7 3.09 -6.62
5/15 9.27 4.94 3.74 2.67 -5.87

His two seam/sinker has been a little flatter than it was in 2014.  His four seamer seems to be moving a bit more vertically.  Other than that, he seems to have gotten pretty similar movement on his pitches so far this season.

Let's try horizontal movement....

Month Fourseam Sinker Change Slider Curve
3/14 -5.91 -9.46 -11.97 2.37 8.48
4/14 -5.71 -8.19 -9.28 2.35 8.98
5/14 -6.11 -7.59 -9.33 0 7.81
6/14 -6.27 -9.38 -9.21 0 6.99
7/14 -6.03 -8.51 -8.4 0 7.23
8/14 -5.92 -8.57 -8.95 0 7.21
9/14 -6.76 -9.87 -9.47 0 7.21
10/14 -6.19 -8.7 -8.71 0 6.13
4/15 -5.5 -8.52 -8.85 0.35 8.21
5/15 -5.6 -10.66 -8.59 1.91 7.46

Maybe we see a little more here.  His fastball has lost about half an inch of horizontal movement from last season.  His two seam/sinker is moving a little more horizontally than it did for most of last season.  The changeup's horizontal movement seems to be down a little.

All in all, there's not really any massive difference that we see here between his stuff in 2015 and his stuff in 2014.  He just hasn't been putting the ball where he wants to as effectively.

Swinging Strike rate

I don't know what Greg's got up his sleeve for the counterpoint, but I would certainly think his swinging strike rate might come into play.  Strasburg has an 11.0% career swinging strike rate.  It's never been below 10.7% in a full season.  This year, it's 7.0%. Since I'm basing most of my argument on the fact that Strasburg's stuff has been there this season, it's a little concerning that his swinging strike rate is just 63.6% of his career rate.

Hitters are making contact on 90% of the pitches that they swing at in the zone.  They're making contact on an utterly ridiculous 73.6% of pitches that they swing at that are outside the zone against him.  His career O-Contact% is 57.0%.  A 73.6% O-Contact% is the kind of thing you expect to see out of Doug Fister (72.0%) or Mark Buehrle (72.1%).  Those are guys that go up there trying to induce weak contact who will occasionally strike a batter out.  Strasburg is one of the top strikeout pitchers in the league, so he's missing a big part of his game.

Outside of the command issues, it's difficult to explain why Strasburg is allowing so much more contact this season than he ever has before without speculating.  As we discussed above, his stuff this season has looked just as good as it did last year.  Is it possible that Wison Ramos isn't calling such a great game when he's on the mound?  (Yes) Is it possible that he's tipping his pitches?  (Maybe)

Why will Strasburg be more effective in the second half?


Stephen Strasburg is eligible to come off the disabled list on Sunday, but he'll obviously go through some type of rehab stint.  Pitchers are eligible to spend as long as thirty days in the minors on a rehab stint before they have to be removed from the disabled list and optioned to the minors.  Regardless of whether the neck was really the issue the whole time or whether it just gave them the excuse to send Strasburg to the disabled list so that they could buy time to figure out what the problem was, the Nats should take full advantage of this.

Strasburg has dealt with mechanical issues all season long.  Working with him in the bullpen hasn't solved the issue.  He'll get game situations in a lower pressure environment during his rehab stint.  He'll face live hitters.  There will be opportunities for him to work out of the stretch with runners on base and deal with other distractions.  It will be just what the doctor ordered.

They shouldn't call him up and end the rehab assignment if he has one dominant appearance or two very good appearances.  They should let him stay down for four or five appearances and get comfortable refining and repeating his mechanics.  As long as he can get those mechanical issues taken care of, he'll be fine.

His stuff hasn't gone anywhere.