Stephen Strasburg, in just over one full season’s worth of work over his career (263.2 innings), has put up scary numbers: 22–11 record, 3.00 ERA, 2.48 FIP, and 321 strikeouts. His stuff ranks at the top of the charts, with a fastball that averages 96 mph and the majors’ nastiest changeup by whiff rate.
Still, in 47 starts, Strasburg has never pitched a complete game. In fact, he has never even pitched into the eighth inning of a start! He’s pitch exactly 7 innings eight times, and no more than that. Most of the people in attendance at the Nationals’ opener this year, myself included, expected him to come out for the 8th inning of a game in which he’d thrown 80 pitches and surrendered no runs. Davey Johnson, citing the extra toll exacted by an opening day start, sent out Tyler Clippard, instead.
One of the criteria that the starting pitchers who really dominate leagues for years at a time—your Justin Verlanders, Roy Halladays, Randy Johnsons, Greg Madduxes, etc.—is the ability to go deep in games and save bullpens. Can Strasburg join this group?
Odds are, he’ll join sooner or later. He can throw many pitches in a game and has done so before, topping 100 pitches 11 times, with a career high of 119. However, he was limited in past by injury and recovery/prevention thereof. He is also still learning to be a pitcher at the young age of 24. As he matures, there’s little reason to doubt based on his in-game performance that he can become a highly durable pitcher. (His mechanics may stop him, but that’s another topic for another day.)
Pitch efficiency—walks and strikeouts
Nationals pitching coach Steve McCatty has his own ideas of how to keep pitchers in games longer. It includes "pitching to contact" and avoiding strikeouts in the belief that Ks make a pitcher throw more pitches to get outs. This assessment has been debunked by many people, including our own Spencer Schneier and Jeff Sullivan. If anything, strikeouts can save a pitcher if he surrenders a high BABIP, guaranteeing himself outs when he would normally risk a poor defense or bad luck interfering with the course of a game.
I decided to use pitches/out as the standard measure of efficiency on a sample consisting of all pitchers with 200 innings as a starter since 2010 (n=168). Regressed against innings/start, strikeouts had an extremely statistically significant but very small r2 (.09), walks did not have a significant correlation, and pitches/out had a significant and strong correlation (-.63). We might be on to something.
I reaffirmed the irrelevance of strikeouts in pitch counts in my own research, finding an r2 of .02 between K/9 and pitches/out. McCatty is simply wrong. Walks, however, had a highly statistically significant and moderately strong .25 r2, pointing to the intuitive conclusion that walks are bad for pitch counts. For a pitcher with poor control and a high walk rate, that’s something you’d target immediately to get his pitch count down and go deeper into games. But Strasburg’s walk rates are not a concern. His BB/9 ranked 49th out of those 168 pitchers, and his BB% was 57th.
So despite his above-average control and amazing arsenal of pitches, Strasburg actually works pretty hard to get outs—maybe harder than he ought to. His pitches/out is 5.31—ranking him just 76th out of 168. That’s a lot lower of a rank than I expected.
Beyond walks and strikeouts
If Strasburg’s strikeouts and walks are not weighing down his pitch efficiency, it could have something to do with his pitch sequencing and strategy within at-bats. Incidentally, this is an adjustment he might be already making. Strasburg has worked this spring training on using his filthy changeup earlier in games and counts, and to different sides of the plate. He’s also continually fine-tuning his fastball command, which can occasionally betray him.
Still, the biggest factor that has limited Strasburg’s outings has been concerns over his arm. He was a rookie in 2010, rehabbing his injury in 2011, and under a careful work limit last year. If he had gotten eight more outs and qualified for the league leaders last year, his 93.1 pitches per start would have ranked him 82nd out of 87. Pretty much all of the pitchers we’d recognize as "aces" averaged over 100.
In 2013, for the first time, Strasburg will be free to pitch his arm out the way a true "ace" does. He already tested himself in Cincinnati this Sunday with 108 pitches. And with all of the other requisite tools in place to be a successful starter, all signs point to Strasburg eventually becoming the kind of guy who can churn out complete game shutouts on a regular basis.