Where are the strikeouts for Sam Coonrod?

We’re 20 innings into Sam Coonrod’s major league career. That’s not enough of a sample to make any serious claims of who he’ll be, but it is enough for a first impression. So far, the impression has been… good? In those 20 innings, he’s given up just six runs while allowing 2 of 10 inherited runners to score. Both of those came on Adam Jones’ three-run homer in Arizona.

He’s been pretty good at preventing runs, but for a guy who can throw 98 mph, he hasn’t gotten a ton of strikeouts. Including Thursday’s outing where he struck out two in a perfect inning —

— Coonrod has struck out 14 batters, or 6.3 strikeouts per nine innings. It’s hard to succeed if you’re striking out batters like Dereck Rodríguez and walking people like Reyes Moronta.

Again, it’s only 20 innings. Just because Coonrod hasn’t struck a ton of batters, it doesn’t mean that he won’t in the future. In Triple-A this year, he maintained a Morontaean strikeout rate. We’d expect his strikeout rate to fall a bit going from the minors to the majors but not get cut in half. But again, it’s only 20 innings; and, a Pitching Ninja spotlight.

So far, Coonrod’s swinging strike percentage is 9.3 and that puts him in the company of low 90s Jeff Samardzija. His CSW (called strikes and whiffs over total pitches) is 25.7%, which is three percentage points below league average. Using Mike Podherzer’s expected strikeout percentage, which calculates how many batters a pitcher should strike out based on swinging strikes, fouls, and called strikes, Coonrod’s strikeout rate should be 21 percent (if I did the math right) instead of 18.2. That would roughly put his strikeouts per nine in the 8’s, but that would still be low considering Coonrod’s stuff.

If there’s one pitch getting in the way of his strikeout numbers, it’s the sinker. According to Baseball Savant, Coonrod throws four pitches: four seam, sinker, curveball, and changeup. He’s thrown more sinkers than four seamers this season, and it’s been an effective pitch at getting hitters out. It hasn’t been a swing and miss pitch, however.

Hitters generally have an easier time making contact with sinkers. It’s one of the reasons the league as a whole is moving away from the pitch in favor of sliders and four seamers. Several pitchers have benefited from dropping the sinker including Gerrit Cole, Lucas Giolito, and Liam Hendriks. It’s not always so simple as just throwing fewer sinkers. Those three pitchers also added spin to their fastballs and in Hendriks’ case, he added three mph to his fastball.

Coonrod has the velocity and spin to live with the four seamer, but he might not have the command. Pitchers are generally able to spot their sinkers better and that’s been the case for Coonrod. Here are the locations for his sinkers this year.

Most of the time, he hits the strike zone and he’s been able to concentrate them on the armside part of the plate. Here are the locations of his four seamer.

His location has been much more sporadic and he’s just as likely to miss the strike zone. Unless he starts throwing his changeup or curve for strikes, he needs the sinker to get ahead of batters.

If Coonrod doesn’t change anything, I would expect his strikeout rate to rise on its own. So long as he depends on the sinker, it might not rise to elite or even above average levels. If the sinker continues to keep hitters on the ground, it’s not necessarily a bad thing.