Mitch Keller appears to be on the rise

When Mitch Keller was taken by the Pittsburgh Pirates in the second round of 2014 MLB Amateur Draft, hopes were high. Since his arrival in Pittsburgh in 2019, results have been mixed.

I remember seeing Keller pitch in his debut against the Cincinnati Reds, a game that my wife and I were in attendance for during one of our wedding anniversaries. He got shelled. Keller went four innings in a losing effort, giving up six runs on seven hits over four innings. It was not a fun game.

During the shortened COVID year, certain metrics inspired confidence, like the righty’s 2.91 ERA over five starts. But other numbers, like FIP, suggested a more dire state of affairs: 6.74. In other words, for the events that Keller controlled, he floundered.

Some predicted a regression heading into 2021, myself included, and were (unfortunately) correct in our assessment. Over 23 starts, Keller saw his ERA balloon to 6.17, and for many, it seemed like the end of the road for the one-time ace hopeful.

Then, in his age 26 season, Keller pitched the best he’d ever pitched in a big league uniform. Finally coming into his own, he posted a respectable 3.91 ERA over 29 starts, and a well in-line 3.88 FIP to boot. He saw his walk rate decrease and his WHIP drop drastically. Suddenly, Keller looked like a solid middle-of-the-rotation type pitcher.

Now coming into 2023, many are eagerly awaiting Keller’s performance, a departure from past expectations. Thus far in Spring Training, in seven innings of work, Keller sports a 3.86 ERA and a very solid 1.14 WHIP. Small sample, sure, but right now, that’s what we have to go on.

So how can we evaluate Keller during the 2023 campaign? Let’s start with what Rob Biertempfel outlined regarding the pitcher’s arsenal. Biertempfel described it as a “cutter-gyro-thingamajig,” and while Keller himself doesn’t quite know how to categorize it – “I don’t even know (what to call it). We’re having trouble deciding” – Biertempfel compared its movement to teammate JT Brubaker’s slider.

This isn’t the first time we’ve heard of Keller toying with what is more of less an unidentifiable pitch. It speaks to the level of the pitcher’s creativity.

Keller’s pitch-mixing has perhaps helped to create his best strikeout rate since his first season, while pushing out his lowest walk rate since that same year. In order to examine whether or not Keller can continue to build on his efficacy, it will be important to watch if those numbers continue to trend in positive directions.

The Pirates have an interesting mix of veterans, youngsters and pitchers with some experience on their staff; still, Keller’s progress still tends to compel the highest number of viewers to see how he’s performing and progressing. While it’s unclear that Keller can ultimately anchor the rotation, his continued ascendancy will be monitored closely.