BRADENTON, Fla. — When Tyler Glasnow described his own failed Pirates career last March, from pounding sinkers to the alarming lack of recourse when things went awry, one of the random topics he tackled was the fate of Mitch Keller, whom Pittsburgh drafted three years after Glasnow.
Although Keller was coming off a rookie year in which he put up some decent numbers but struggled with a .475 batting average on balls in play (BABIP), Glasnow said he felt Keller would quickly blossom into a front-of-the-rotation starter.
“I bet he’s gonna go shove,” Glasnow told the Post-Gazette, using baseball slang for pitching well. “He’s disgusting. He’ll figure it out.”
It was a positive endorsement at the time, one former Pirates pitching prospect pumping the tires of a current one. Now, it feels a little freaky.
Keller has made 16 big league starts for the Pirates. Glasnow made 17 before Pittsburgh traded him to Tampa, though he did pitch more out of the bullpen.
To this point, Keller remains equal parts elite prospect and question mark, the same as Glasnow before he was traded. On one hand, it’s reasonable to see Keller starting on opening day in Chicago or the home opener the following week back at PNC Park.
The 24-year-old also began Monday’s game with a 21.60 ERA, having allowed 12 earned runs on 15 hits, six for extra bases and three landing over the fence. He ended it having delivered a fairly encouraging performance, one where the results — 3 1/3 innings, four runs allowed — didn’t necessarily express how well he pitched.
“[Monday] was a big step for him because his last few starts have not been good,” Pirates manager Derek Shelton said. “The fact that he was able to bounce back and use his fastball in the zone was definitely an encouraging sign.”
Fastball command is a key for every pitcher, but perhaps even more so for Keller, who threw 50 of his 71 pitches against the Orioles for strikes, including 25 of 37 fastballs.
If Keller can get ahead in counts, his breaking stuff is outstanding, and it allows him to induce weak contact or pitch for strikeouts the way Glasnow was finally allowed to do in Tampa. However, you have to get there first.
“Just going in with the mentality just to fill it up, and I thought I did that pretty well,” Keller said of keeping his heater in the strike zone.
As for the comparison between the two, it’s extremely close, as Glasnow pitched to a 5.79 ERA compared to Keller’s 5.81.
Home runs? Glasnow averaged 1.3 per nine innings, the same as Keller. Meanwhile, Glasnow had a 1.705 WHIP compared to 1.651 for Keller. Strikeouts (10.5 to 9.7) and walks (4.4 to 5.8) per nine innings paint Keller in a slightly more favorable light, but the point remains the same.
The Pirates never could figure out what to do with Glasnow. After significant pitching and developmental changes under general manager Ben Cherington, starting with pitching coach Oscar Marin and a modernization of the entire program, they can’t afford to whiff the same way on Keller.
For the Pirates to take meaningful steps forward both this season and beyond, Keller must thrive in Pittsburgh — not somewhere else the way Glasnow did with the Rays, pitching to a 1.78 ERA the first full season he was allowed to do his job a different way.
There were several factors that contributed to Glasnow’s breakout, but two good starting points involved his four-seam fastball and curveball.
After leaving, the Rays helped Glasnow find more spin and velocity, the same way the Pirates are starting to do with Keller (and other pitchers) now. After averaging 94.2 mph and 2,458 rpm with his four-seamer as a rookie in 2016, those numbers were 96.9 mph and 2,939 for Glasnow last season.
Meanwhile, the weighted on-base average (wOBA) Glasnow’s curveball produced reached a career-best .163 in 2019 and a not-too-shabby .203 in 2020. Glasnow also threw his curve 10-15% more than he did in Pittsburgh.
It’s not that simple with Keller, who has a different array of pitches. For example, Keller has two terrific spin pitches compared to Glasnow’s one and has already shown solid spin rates on his curveball and slider; the lowest for either was Keller’s slider in 2020, which averaged 2,425 rpm.
So far this spring, the fastball and changeup have been front-burner issues for Keller, who actually threw a couple changeups Monday to mixed results. Two were hit for singles, although he also struck out third baseman Rio Ruiz swinging on a nice one early.
“I was encouraged by it,” Keller said. “It’s feeling better throughout spring, so I think it’s going to be a big weapon for me.”
Not necessarily like Keller’s slider, on which opponents had zero hits last season despite a 21.9% usage rate, but that’s why Keller has been worrying about different things, the fastball and changeup chief among them.
Even on Monday, Keller ran his fastball up to 98 mph early, then was sitting around 94 mph late, a change partly attributable to building strength but also the process of pacing oneself.
Big picture, the Pirates and Keller know there’s a delicate balance to strike here, between speed and spin, as well as quality pitches both in and out of the zone. The trick, like it was for Glasnow, will be bringing it out.
If they do, the Pirates might have a legitimate ace and a bunch of clout with younger pitchers. If they don’t, the questions will undoubtedly persist.
Jason Mackey: jmackey@post-gazette.com and Twitter @JMackeyPG.
First Published: March 22, 2021, 1:54 p.m.
