Jordan Zimmermann, in a starting rotation with Stephen Strasburg and Gio Gonzalez, doesn’t get much attention. But did you know he led the Nationals pitching staff in quality starts last year? And that he leads the major leagues in WHIP this year? Zimmermann’s path to success, especially so far this year, defies basic sabermetric assumptions and is worth examining more closely.
Zimmermann is built like a power pitcher. He’s a sturdy 6’2”, 220 lbs., and he has a fastball that averages better than 94 mph. He has a hard slider and much-improved curveball as his secondary pitches, as well as an occasional changeup. He has the pure “stuff” to strike out 200 batters a season.
Steve McCatty, Zimmermann’s pitching coach, does not want him to be a strikeout pitcher. McCatty believes that strikeouts are a bad goal for pitchers because they drive up pitch counts, while carefully “pitching to contact” is the correct approach. Zimmermann said recently, “You try to make nasty pitches in the dirt, and if the hitters don’t swing, you get them back in the count and you end up throwing six or seven pitches to a hitter.”
In the offseason, Ben Lindbergh looked at Zimmermann’s high fastball usage, high foul rate, and low strikeout rate, combined with mediocre pitch efficiency, and concluded very reasonably that Zimmermann ought to try using his breaking stuff more and feel free to pitch outside of the strike zone to get more K’s.
On the whole, after all, statistics show McCatty’s assumptions are wrong. But Zimmermann first month this season has mostly been a vindication of the McCatty system.
Zimmermann’s strikeout rate is well below average at 5.5/9 innings and 16 percent of batters overall. A low strikeout rate is bad for pitchers because it places pressure on them to get outs through balls in play, or so the theory goes. Zimmermann has somehow been able to hold batters to a .188 BABIP this year—including a paltry .213 on pitches inside the strike zone. His groundball rate is up to 51 percent this year, from 43 percent last year. He’s also held himself to a tiny walk rate of 1.4/9 innings, or just 4.2 percent.
The most amazing part of it is that Zimmermann actually is pitching to contact when he gets these outs. His fastball usage has increased this year, and so has the fastball’s groundball percentage. Sixty-six percent of his pitches have been strikes, and 55 percent have been in the strike zone (while the league average is just 49 percent). He’s also been able to cut down on his foul/swing rate from last season, when it was one of the league’s highest. His home run rate is also quite low, at just 5.4 percent of the fly balls he’s allowed, or two in 44 innings.
What that means is Zimmermann has found, at least for now, his holy grail. He’s needed just 4.36 pitches/out, meaning he could record a complete game on just 118 pitches given an average performance this year. Indeed, he’s already thrown two complete games this year, including a one-hit shutout of the Cincinnati Reds that is undoubtedly one of the greatest games pitched in Nationals history.
What this means is that hitters are seeing the pitches out of Zimmermann’s hand, convincing themselves they can hit the ball hard, making contact, and then consistently making outs. It’s an extremely difficult pattern to maintain.
For Zimmermann to continue his success in the same fashion, mechanical consistency and command of his pitches will be essential. If he loses the ability to spot his pitches, batters will likely become less aggressive—thus requiring more pitches to record an out. He also makes himself dependent on a defense that has had a couple of hiccups this year. If the .188 BABIP figure is a result entirely of luck, rather than skill, Zimmermann’s strategy would eventually become a great deal of “pitching to contact” with runners on base—a dangerous way to live, when a guy has the stuff to strike guys out. His BABIP will regress, but whether or not it will go back to league average and suggest a change in strategy will tell us whether Zimmermann has entirely been lucky so far, or whether he’s really figured something out.
A good test of Zim’s strategy comes tonight against the Tigers. Detroit’s hitters have good plate discipline and good contact rates, as well as good power. If Zimmermann’s aggressive strike throwing gets hit hard early, he may need to adjust and look for the strikeout with his breaking pitches. But if he can hold up against the likes of Miguel Cabrera and Prince Fielder, he will demonstrate definitively that he has found a formula that could soon make him a household name.
Thank you for reading
This is a free article. If you enjoyed it, consider subscribing to Baseball Prospectus. Subscriptions support ongoing public baseball research and analysis in an increasingly proprietary environment.Subscribe now