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The case for: Nationals' starter Stephen Strasburg

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He's not acy enough! He's the Nats fourth or fifth best starter! Maybe they should take him out of the rotation! To quote (of all people) Susan Powter, "Stop the insanity!" He isn't having his best season (particularly on the road) in 2014, but since reaching the majors in 2010, here is where Stephen Strasburg ranks among starting pitchers in some key statistical categories. ERA: 14th FIP: 5th xFIP: 1st.


We all heard the hype train rolling into town when the Nationals were preparing to select Stephen Strasburg with the number one pick in the 2009 draft. His fastball was going to put Nolan Ryan's heater to shame. He had the potential to develop a changeup that Pedro Martinez would be jealous of. His breaking ball also profiled as yet another potentially devastating out pitch. By most accounts, he would at least threaten to supplant Walter Johnson as the greatest pitcher a D.C. squad has ever seen.

Five years later, the Nats have been left with a pitcher who has merely been excellent rather than a player whose path is leading to a unanimous first ballot Hall of Fame election. Where did the Nats go wrong? The shame!

Appreciate What We Have

Since the start of the 2010 season (Strasburg's rookie year), let's have a look at where Strasburg ranks among all MLB starting pitchers in some key categories.

Statistic Strasburg's Numbers MLB Rank
ERA 3.15 14th
FIP 2.84 5th
xFIP 2.74 1st
SIERA 2.78 1st
WHIP 1.11 11th
K/9 10.51 2nd
BB/9 2.41 51st
HR/9 0.82 42nd
fWAR 13.8 25th
fWAR/100 IP 2.34 10th

So... What do we take from those numbers? He hasn't been the best starter in the majors, which the hype train led us to believe he would be. He's been great in terms of traditional rate stats like ERA and WHIP. He's been excellent in terms of FIP, which normalizes BABIP.  He's been the best in the league by xFIP, which also normalizes HR/FB rate to 10.5%. He also leads the majors in SIERA (Skill Independent ERA... I'll link a description), which is another component ERA that attempts to measure pitchers based on their underlying skill.

(Why) Is he (really) struggling in 2014?

Of course, some of the problem isn't what he has done since arriving in D.C. It's what he's doing right now. Here are his 2014 ranks in those same categories (minus fWAR/100 IP):

Statistic Strasburg's Numbers MLB Rank
ERA 3.68 51st
FIP 3.00 18th
xFIP 2.53 3rd
SIERA 2.63 5th
WHIP 1.23 40th
K/9 10.71 3rd
BB/9 2.01 26th
HR/9 1.04 68th
fWAR 3.0 18th

Once again, we see that stats like FIP, xFIP, and SIERA love him. Perhaps he isn't ranked quite as highly in those statistics as he has been over his career, but statistics that look at his underlying skill and eliminate BABIP and HR/FB rate say that he's having yet another excellent season. Unfortunately, he's had massive problems with both of those statistics. Let's see if we can find a reason why.


Strasburg has allowed a .341 BABIP in 2014, which is fourth highest in MLB. The league average BABIP is .292.  Strasburg's career BABIP is .302. While luck is often brought up when BABIP is discussed, I'm not ready to pin it all on luck. First, let's have a look at his batted ball charts.

2010 .319 1.51 20.5% 47.8% 31.7% 7.8% 9.8% 6.5% 0.0%
2011 .242 1.05 26.2% 37.7% 36.1% 9.1% 0.0% 8.7% 0.0%
2012 .311 1.34 22.7% 44.2% 33.1% 9.2% 11.5% 7.4% 0.0%
2013 .263 1.66 17.5% 51.5% 31.0% 8.3% 11.1% 8.8% 0.0%
2014 .341 1.45 24.0% 45.0% 31.0% 7.0% 14.1% 7.5% 7.7%
Total .302 1.47 21.3% 46.8% 31.8% 8.2% 11.3% 7.9% 2.9%

I've led with his BABIP for each season, which we can see has really fluctuated. Again, in a luck neutral environment, we can usually expect the league average BABIP to be somewhere between .290 and .295. There's some question as to how much a pitcher can really control this, but we can certainly expect that the type of hit will have an effect. For many of you, this will be nothing new:

  • Line Drives (LD%) are the most likely to result in a hit.
  • Ground balls (GB%) fit somewhere in the middle.  They're far less likely to result in a hit than a line drive, but more ground balls find a hole on the infield than fly balls.
  • Fly balls (FB%) are the most likely event to result in an out.  The majority of fly balls tend to find a glove and get caught.  A few more (generally in the 10-10.5% range) find their way over the fence and don't count towards BABIP because they are home runs.

Since Strasburg combined for just 17 league starts (SSS) in 2010 and 2011, I'm not going to pay a lot of attention to those seasons. Instead, let's focus on the past three seasons, where Stras has had a slightly high .311 BABIP followed by a very low .263 and then this current season's ridiculous .341. What do the components tell us?

  • We'll note that his 2012 LD% was a touch high (22.7%... league average was 20.9% that year), so we should expect that this could have helped lead to a higher than average BABIP (.311... check!).  His 2013 LD% was likely an outlier based on everything else we've seen from Strasburg in his career, but his LD% was 3.7% lower than the league average, which likely helped keep his BABIP extremely low (.263... check!).  In 2014, his LD% has been a career worst 24.0%, which is 3.4% higher than the league average.  We're seeing the results in his .341 BABIP (again, check!).
  • Save for the 2013 season, his GB% has been roughly league average (45%).  This should lead us to believe that his GB% isn't necessarily the problem.  It was instrumental in the 2013 season that appears to be an outlier, but his GB% has been neutral in 2012 & 2014.
  • His FB% is actually a touch low, which would likely hurt his BABIP a touch as well (again, this is the most likely BIP to become an out).  The kicker for this season, though, is that more of those fly balls are going over the fence.  While those home runs don't raise his BABIP, the combination of a low fly ball rate and a high HR/FB rate means that fewer of those fly balls he's allowing are turning into outs.

HR/FB Percentage

Strasburg has owned a slightly high HR/FB rate for the past few seasons, but it's typically been less than 1% above the league average (~10.5%). This season, his HR/FB rate is at 14.1%. This may be a bit inflated after the ridiculous 80% HR/FB rate in Friday's start at Atlanta, but it's still one of the things that may be skewing a surface stat like ERA farther above what his FIP and (in this case) xFIP would suggest we should expect of him moving forward.  Strasburg's 14.1% HR/FB rate is the seventh highest in the majors this year.

Apart from luck, what could be causing his problems with BABIP and HR/FB rate? Let's look at the simple answer.

Fastball Velocity/Effectiveness

While simple poor luck has to account for some of the BABIP (and maybe even a small portion of the HR/FB rate), there is another factor we have to consider. Strasburg's average fastball velocity has declined a bit in each season of his career so far.  This isn't really all that unusual, and he's still one of the hardest throwers in the league. In fact, I was watching the Royals-A's game last night (Yordano Ventura was pitching for Kansas City). The A's broadcast showed a graphic of the pitchers with the top average velocity in MLB this season.  Strasburg was sixth.

In 2014, he's averaged 94.5 MPH (down from 95.2 MPH last season). While Pitch Values indicate that the gradual decline in velocity hadn't really affected his fastball's effectiveness much in the past few seasons, that effectiveness has completely fallen off of a cliff in 2014. Here's another visual showing the performance in terms of Runs Above Average with Strasburg's three primary pitch types:

Season wFB wCB wCH
2010 5.3 2.6 3.6
2011 5.8 1.7 2.2
2012 4.6 9 3.4
2013 6.4 13.2 8.7
2014 -11.1 3.5 10.2
Total 11 30.2 28.1

I've left the curveball and changeup in this table so that we can see just how effective that changeup has become. It's devastating, and has gradually become his best pitch. He's still using his curveball effectively, but not as effectively as he had in the past two years. The fastball, however, has gone from a pitch that has always been worth a handful of Runs Above Average to a pitch that has been one of the worst in the majors in 2014. In fact, among 89 qualifiers for the ERA title, Strasburg's fastball ranks 83rd in Runs Above Average.

Strasburg has thrown the fastball less often this season (59.1%) than he has in the past (61.7% career), but he still throws it well over half the time. Most major league pitchers do. If opponents keep squaring it up, that's likely to lead to continued struggles.

As for movement, all of the Pitchf/x data that I can find seems to indicate that he's gained a little more movement on his fastball (we might anticipate more movement to compensate for the drop in velocity), but it hasn't been all that significant. He's had slightly more average vertical movement (8.97 vs. 8.84 from 2012-2013) and horizontal movement (5.96 vs. 5.32 from 2012-2013) in 2014.

This doesn't really explain a lot (even to me as I write it), but it does leave me wondering just how the pitch has gone from 6.4 Runs Above Average (23rd in MLB) in 2013 to -11.1 Runs Above Average (or 11.1 Runs Below Average, if you prefer) and 83rd best among 89 qualifiers with a 0.7 MPH drop in velocity.

Plate Discipline Against

Season O-Swing% Z-Swing% Swing% O-Contact% Z-Contact% Contact% Zone% F-Strike% SwStr%
2010 36.9% 60.2% 47.1% 57.2% 85.0% 72.8% 43.8% 60.2% 12.5%
2011 33.6% 67.7% 51.0% 63.5% 85.3% 78.3% 51.0% 71.6% 11.0%
2012 29.5% 62.2% 44.3% 55.9% 84.9% 74.3% 45.3% 62.3% 11.2%
2013 30.8% 63.9% 45.6% 59.1% 86.4% 76.2% 44.7% 59.8% 10.6%
2014 36.1% 63.3% 48.1% 58.7% 86.3% 74.7% 44.1% 65.0% 12.0%
Total 32.7% 63.0% 46.3% 58.1% 85.7% 75.0% 44.9% 62.4% 11.4%

I'm going to spend very little time on this section because the data doesn't really explain much of anything.

  • Opponents are chasing more often than they have against Strasburg the past two seasons.
  • They're not making a significantly higher amount of contact either on pitches in or out of the zone, so this should actually be a positive.
  • Stras is actually getting more fist pitch strikes over than he did in either of the past two seasons, which defies the myth that he's been falling behind and throwing opponents challenge fastballs that get crushed.
  • His swinging strike rate has been as high as it's been since his rookie season in 2010.


We'll show you a series of tables here detailing "two pitchers." They are Stephen Strasburg at home and Stephen Strasburg on the road. I'm going to show all three seasons in which he's made at least 28 starts. We'll see that the road woes haven't been limited to this season, but we'll also see that he's more than capable of pitching well on the road.  We're going to work backwards, since everyone's focused on this year.


Location GS IP ERA FIP xFIP WHIP K/9 BB/9 wOBA Wins Losses
Home 13 86.0 2.41 2.18 2.10 1.06 11.72 1.47 .273 7 2
Road 12 70.3 5.25 4.00 3.05 1.44 9.47 2.69 .358 1 8

It's really hard to explain what the problem is. There's the narrative that he's found a comfort zone with how the mound is kept up at Nationals Park that just isn't there on the road. I don't really buy into it that much, but it at least tries to provide some explanation. Ordinarily, I'd just chalk it up to randomness and a bit of a small sample size. Whatever the explanation is, Strasburg has been a completely different pitcher on the road than he has been at home this season.

While his three worst starts (which have accounted for 20 runs in 14 innings) have come on the road this season, it's not like those starts are overwhelming a bunch of shutdown efforts. Strasburg has allowed three or more runs in nine of his twelve road starts. He's allowed three or more runs in just four of his thirteen home starts (2 home and 1 road start came against the Braves, who have gotten to Strasburg for 17 runs [14 earned] in just 14.3 innings). Unfortunately, when we look at 2013, we see similar results even if they are to a slightly lesser degree.


Location GS IP ERA FIP xFIP WHIP K/9 BB/9 wOBA Wins Losses
Home 15 99.0 1.73 2.38 2.64 0.87 9.82 1.64 .232 5 4
Road 15 84.0 4.50 4.19 3.75 1.26 8.89 4.09 .305 3 5

Yes. Those are the same two situations in 2013. Last season, Strasburg was among the very best pitchers in baseball when he was pitching at Nationals Park. He was basically Dan Haren (last year's Nats version... not peak Dan Haren) when he was pitching on the road. We'll have to go back to that magical 2012 season to attempt to debunk this myth that he can't pitch on the road.

Location GS IP ERA FIP xFIP WHIP K/9 BB/9 wOBA Wins Losses
Home 14 77.3 3.49 3.41 2.90 1.18 10.24 2.21 .307 6 3
Road 14 82.0 2.85 2.28 2.72 1.13 11.96 3.18 .266 9 3

The situation reverses itself a bit here. Strasburg was outstanding on the road in 2012.  In fact, his Road ERA ranked seventh among qualified starters. His Road FIP was .55 better than second place finisher Homer Bailey. His Road xFIP was .37 better than second place finisher (and Cy Young winner) R.A. Dickey. Strasburg was merely really good at home in that season rather than the otherworldly numbers he's posted in Nationals Park the past two seasons, but he showed that it's possible that he can pitch effectively on the road.

What can we draw from this?

I'm not really sure. The expectation is that any pitcher is going to be a little better at home than they are on the road. I checked the league average totals for the past few years and did find this to be true. However, the league averages show that (generally) a pitcher should have an ERA, FIP, and xFIP that's roughly 0.20 higher on the road than it is at home. The wOBA allowed is about .010 higher on the road than at home. Of course, league average doesn't mean that it works the same way for every player. The majority will probably be moderately close to the league average. There will be extreme cases on both sides of the ledger that balance each other out and help to find our mean, though.

Unfortunately, Strasburg's splits the past two seasons have been beyond extreme. It's great that he makes half his starts in Nats Park, where he looks like a future Hall of Famer. It's just astounding (and a bit inexplicable) that he's been so much worse on the road the past two seasons. For the rest of the regular season, there's not a whole lot that the Nationals can do about this. As we would assume based on the fact that they've played the fewest games in the majors (116, tied with Detroit), there aren't a lot of off days remaining on the schedule. In other words, there's probably not a lot of room to maneuver the rotation to try and maximize his opportunities to start at home for the remainder of the regular season.

What should we expect the rest of the season?

Assuming the rotation remains in the current order for the rest of the season, Strasburg should have nine starts remaining. Five would come at home. Four on the road. Here's what we're looking at:

Date Opponent Opp. Runs Rank Opp. wOBA Rank
8/14 @NYM 23rd 28th
8/19 vs. ARI 14th 17th
8/24 vs. SF 21st 25th
8/30 @SEA 24th 27th
9/5 vs. PHI 22nd 29th
9/10 vs. ATL 28th 23rd
9/15 @ATL 28th 23rd
9/20 @MIA 17th 20th
9/26 vs. MIA 17th 20th

To be honest, there isn't a start remaining that shouldn't at least be somewhat favorable based on the opponents' offensive ranks. Of course, we know that those last four could prove tricky for Strasburg, even if neither the Braves nor Marlins are really paper tigers offensively. Everything points to the possibility of him posting three or four dominant outings in his five starts leading up to his next meeting with Atlanta. He'll make three of those next five starts against mediocre offensive teams (The best offensive team he'll face is Arizona, who has lost their best hitter [Paul Goldschmidt] for the year) at home. The other two will be against below average offenses. While they'll be on the road, they're in pitcher-friendly venues.

This stretch will hopefully get Strasburg rolling before he'll have back to back starts against an Atlanta team that has had his number no matter where he's faced them (and how below average they've been offensively overall) this season. He'll close out with two starts against Miami.  Both of the series with the Marlins may still mean something for both teams. Strasburg's splits have really shown against the Marlins in his career. He's 2-4 with a 6.90 ERA and 1.63 against them in Marlins Park*, but 3-1 with a 3.06 ERA and a 0.98 WHIP against them in Nats Park.

* He does miss Sun Life Stadium, where he was 2-0 with 12 shutout innings against the Marlins.

Playoffs? Playoffs?

My general feeling is that the Nats should worry about the playoffs when they've actually gotten there. This obviously hasn't happened yet, but I will opine anyway. With as much data as we have from the past two seasons, it does seem like it would be ideal for the Nats to try and work their rotation around maximizing his starts at home in the postseason. If the Nats were to win the NL East and have home field advantage in the NLDS, it would make all the sense in the world to start him in Game 1 (setting him up for Game 5 at home if necessary... or Game 1 of the next series). If they were to get to the playoffs and start on the road, it might not be the worst idea to start him in Game 3.

Gee... This has been a long breakdown, but when am I going to make the case for Strasburg

My general point is that there's a lot of bellyaching both here and elsewhere on the internet regarding Strasburg. This becomes increasingly prevalent when he throws a lemon, as he did on Friday night. Of course, his two previous starts (one of which was at Miami) where he'd allowed a combined one run and nine baserunners in fourteen innings never happened.  Nope.... It suddenly reverts back to the old "Strasburg is the Nats number five starter" or "Stras should be moved to the bullpen" rhetoric.

The numbers at the very top of this long article show us just how fantastic a starter Stephen Strasburg has been in what equates to about three full seasons of work as a big league starter. He hasn't been as good in 2014 as he was in 2012 or 2013, but his down year has still been pretty solid. There's a little under a third of the season left, and Strasburg should be able to take advantage of this stretch to bring his surface ratios back towards 2012 levels (3.16 ERA, 1.15 WHIP) when all is said and done.

Is he the unquestioned ace (sigh... I was trying not to use it) of the Nationals? No. That's saying something about the rest of the Nats rotation more than it's saying anything about Strasburg, though. Without going into further detail (this is long enough as is), I just went down the list of all thirty teams and determined that Strasburg would probably be the best starter on nineteen or twenty of them. I might be off by one or two teams, but he'd be the ace of over half the staffs in the big leagues.  That's pretty darned good!

It's time for Nats fans to embrace the fact that the Nats have several (I'll say three!) pitchers who have been as good as or better than Strasburg in 2014, because Stras has been pretty good himself.