Mitch Keller Just Might Be The Pirates’ Long-Sought Homegrown Ace

It’s been a rough few years……no make that a decade……no make that a generation for the Pittsburgh Pirates. Sure, there was a small surge during Andrew McCutchen’s heyday, but you have to go back to the Barry Bonds years to find the last true golden era of Pirates’ baseball, and even that fell short of true glory.

There have been lots of missing pieces. Money, for sure. Star power on either the offense, pitching or defensive sides of the game has been in short supply. What the club has really never had was a homegrown pitching staff ace. Sure, Gerrit Cole and Jameson Taillon were premium draft picks with great pedigree, and had their moments in Pittsburgh, but neither met their potential in the Steel City. The trade horror stories are legendary, as they famously chased Chris Archer and threw away Tyler Glasnow and Shane Baz in the process.

Even when you go back to the Bonds Era, they had to trade for budding prospect Doug Drabek to anchor the staff. Really, his cohort John Smiley might be the closest thing to a homegrown staff ace the Pirates have cultivated in the last – gulp – 35 years. Kris Benson? Francisco Cordova? Not aces, but at least homegrown. It’s been a rough go. Even Tim Wakefield skipped out of their minor league camp to an excellent career in Boston.

Mitch Keller had every reason to follow this well-traveled trail of tears. He consistently excelled in the minor leagues only to struggle in the majors. I’m certain that the Tampa Bay Rays and other talent vultures were circling Pittsburgh waiting for the Bucs to finally give up on him.

That 6.17 ERA he compiled in 23 starts in 2021 would have seemed to be the final straw. Out of minor league options, and showing no signs of tangible progress. 2022 started out poorly as well – on this date last year, Keller sported a 6.37 ERA and had made it through the 6th inning in exactly one of his 8 starts.

Then the light gradually started to turn on. He posted a 3.20 ERA the rest of the way, with a 108/46 K/BB in 123 2/3 IP. Now, since this was the 2022 Pirates, this didn’t translate into wins, mind you. He was 4-7 over that stretch, and finished up 5-12, 3.91.

At the end of each season, I grade out each pitch in the repertoires of all major league starters who throw 135 or more innings. I give equal weight to bat-missing and contact management performance relative to the league. Only 17 such pitchers had two fastballs that earned “B” grades or better last season – Keller’s four-seamer earned a “B+”, his sinker a “B”. Though both his curve and slider came in below average at “C+”, he exhibited a solid foundation that he could build upon.

And that’s exactly what he’s done so far this season. Keller has actually added a high quality offering to his mix this season – a cutter. Along with his four-seamer, it’s his most frequently used offering (25% usage rate). Its 10.0% swing-and-miss rate is almost exactly league average, and its pitch-specific 80 Adjusted Contact Score is over a half standard deviation better than average. It gets an interim “B+” grade.

His curve has fallen off a cliff to a “D” thanks to poor bat-missing (6.0%) and contact management (132 Adjusted Contact Score) performance. His sinker has slipped backward a bit from “B+” to “C+” due to a sharp drop to a poor 3.0% whiff rate, while the slider has improved from a “C+” to a “B+” due to solid contact management improvement (to an 80 Adjusted Contact Score).

But the main reason for Keller’s newfound success has been a major jump in class from his four-seam fastball. While four-seamers are the least effective pitch in the game today and are being thrown less than ever, you almost have to have to great one to be a long-term ace. The deGroms, Scherzers and Verlanders say hello.

Keller’s four-seam whiff rate is a rousing 15.4% – no qualifier reached that level in 2022. And he’s managing contact well with it too, with an 83 Adjusted Contact Score. Only one qualifier bested that mark in 2022. No one came close to combining the two feats. The pitch earns an “A+” grade to date, and if I could add another plus, I would.

Overall, a casual inspection of Keller’s advanced pitching metrics aren’t that eye-opening. 9.9% overall swing-and-miss rate? Meh. He rarely induces pop ups and isn’t an extreme grounder generator. That combo can often be the kiss of death. But while his batted ball frequency profile doesn’t stand out, his batted ball authority profile sure does. His average exit speed allowed of 86.3 mph is over a standard deviation better than league average, and his average liner exit speed allowed of 88.1 mph is over two better.

There aren’t that many pitchers who can consistently muffle liner authority, and Keller appears to be one of them. I’m honestly not sure that he can maintain his current K rate, but I’m quite confident in his contact management capabilities. And I really believe in the four-seamer. He’s posted an 88 Adjusted Contact Score to date, with a “Tru” ERA- of 64, right there with his 62 FIP-. Keller looks like a potential Cy Young and Contact Manager of the Year contender.

So Mitch Keller has made it through the fateful career nexus that often led to the Pirates giving up on a promising hurler only to see him blossom elsewhere. The club has recently extended 3B Ke’Bryan Hayes and OF Bryan Reynolds, and it would seem that Keller is next on their priority list. Of course, he is a pitcher, so continued good health is a significant caveat, but the club’s long search for a true ace may have finally come to an end.