The Phillies Have a Brand-New Starting Pitcher

Let me share with you a familiar-sounding story. As a rookie back in 2016, Zach Eflin wasn’t good. There were 181 starting pitchers that year who threw at least 50 innings, and only two of them wound up with a lower strikeout rate than Eflin did. And then as a sophomore in 2017, Eflin wasn’t good. There were 189 starting pitchers that year who threw at least 50 innings, and only four of them wound up with a lower strikeout rate than Eflin did. Yes, there’s more to pitching in the major leagues than generating strikeouts, but Eflin didn’t have anything going in his favor. So he showed up to camp this past spring feeling especially optimistic. In February of 2018, Zach Eflin felt like he was in the best shape of his life.

Admittedly, the story had some substance. Eflin had felt knee pain for most of his life. After the 2016 season, he had surgery to repair the patella tendon in both of his legs. That was good for the pain, but bad for his strength. Eflin didn’t get to have a normal offseason, and he pitched while underweight. The idea this time around was that Eflin would be able to use his lower body. Over the winter, he added something like 20 pounds of muscle to his legs. It all sounded good. But then, best-shape stories always sound good. In the moment, it’s impossible to know who’s going to be better, and who’s going to be the same.

Well, Zach Eflin isn’t the same. He isn’t the same, for the reasons just stated. He’s got the same strikeout rate as Chris Archer. He’s got the same strikeout rate as Jose Quintana. He nearly has the same strikeout rate as Aaron Nola. Eflin is pitching to keep a rotation spot. But in the bigger picture, it’s like Eflin is debuting all over again. His career simply had a false start.

In 2016, Eflin started 11 times. He did the same again in 2017, and so far this year, he’s up to seven. This tells you what’s happening better than anything else:

Eflin hasn’t turned into someone unhittable out there. It’s not like he’s taking a page out of the Max Scherzer book. A couple turns ago, he struck out just two Cubs in 7.2 innings. On Sunday, though, he struck out nine Brewers in six. Eflin is looking like a strikeout pitcher, instead of a pitch-to-contact pitcher. According to the numbers at Baseball Prospectus, out of everyone this year who’s thrown at least 30 innings, Eflin has faced the fourth-toughest average opponent. So, he’s earned this success. And check out a swinging strikeout here of Christian Yelich, who is very good:

That’s a good-looking two-strike fastball. That’s one of the things that Eflin has unlocked. And for the sake of establishing some context, here are year-to-year strikeout rates for every starting pitcher who’s thrown at least 30 innings in each of the last two years, with Eflin in yellow:

This is a sample numbering 122 starting pitchers. Eflin’s strikeout rate is up 11.3 points, which is the second-greatest increase, behind only Gerrit Cole. Cole has gone from good to dominant. Eflin has gone from mediocre to good. Not every breakout has to involve a guy becoming an ace. Eflin is just looking like a major-league starting pitcher. Not bad, for someone originally thought to just be holding a spot for Ben Lively or Jerad Eickhoff.

Behind the strikeouts, there’s been an uptick in Eflin’s stuff. This is where we get to see the health element come into play. This plot is much like the last one, only instead of strikeout rates, you see average fastball velocities. Eflin, again, is in yellow:

Eflin’s fastball is up two miles per hour, which is the greatest increase in the sample. From time to time, now, he can get up to 96, and with the added zip, Eflin has gained added confidence in his four-seamer. As a rookie, Eflin’s four-seam fastball accounted for 34% of his strikeouts. The next year, 28%. So far this year, 58%. Eflin is better at getting to two-strike counts, but he’s especially better at turning two-strike counts into three-strike counts. Eflin is stronger, and healthier, and as a consequence, he’s learning more about his own capabilities. He doesn’t have to pitch to contact anymore, because he’s sufficiently talented to be better than that.

Within Eflin’s delivery, you can see the difference his stronger lower body has made. His emergence is about more than just his stronger legs alone, but that’s been the foundation for everything else. Here are two screenshots, from Eflin’s last home start in 2017, and from his game on Sunday. Conveniently, both times, there’s been a stripe on his pants.

Eflin, this year, is dropping lower on his back leg. In theory, that should allow him to be more explosive off the rubber. And now here’s Eflin just after release:

In the 2018 shot, Eflin’s head and shoulders appear lower. It’s not because he’s otherwise changed his delivery — he’s just getting more forward extension than he used to. He’s pushing off better, releasing the ball a little closer to the plate, and from all of that, more has become possible. Eflin now gets to pitch with a better four-seam fastball, which takes pressure off of his sinker. And with the heater more of a weapon, that opens things up for the slider and change. Eflin, surely, has made a number of tweaks, and he, surely, has benefited from gaining more big-league experience, but the answer to why Zach Eflin is a useful starting pitcher now comes down to the fact that his legs are a strength, instead of a weakness. It’s that strong, consistent delivery that allows Eflin to so frequently stay to the arm-side with his two fastballs:

Eflin’s four-seamer stays arm-side, up, and his sinker stays arm-side, down. His changeup, too, stays arm-side, down, with his slider diving to the other side of the plate. Eflin himself would probably tell you he still has more work to do to improve, and he doesn’t, for example, have a good pitch to get in on a lefty’s hands. But this is still so, so much better than it used to be. It’s not just the premium players responsible for the Phillies hanging out in the race.

Eflin’s going to need to keep pitching well, because Eickhoff and Lively will want spots of their own. Eflin won’t automatically get the benefit of the doubt, like Aaron Nola would, or like Jake Arrieta would. But there’s something appropriate here, since Eflin was acquired for Jimmy Rollins in what might’ve been the first rebuilding move those Phillies made. The Phillies are arriving, with all of their talent coming together. The same could be said of Zach Eflin, who for the first time as an adult can comfortably place his trust in his legs. All of that faith gets channeled up to his arm.

We hoped you liked reading The Phillies Have a Brand-New Starting Pitcher by Jeff Sullivan!

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Jeff made Lookout Landing a thing, but he does not still write there about the Mariners. He does write here, sometimes about the Mariners, but usually not.

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tb.25
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tb.25

That bottom-left pitcher on the 2017-2018 K% plot…

Poor Ty Blach.