Biceps Biceps Biceps.
Seriously. When Michael Lorenzen walks off the mound and gets a close-up on the broadcast, that’s all I can see. The man’s got muscles upon muscles in those arms. I assume that’s why
he’s still pumping mid-90s heat as he enters his mid-30s.
The Royals acquired Lorenzen from the Texas Rangers in July 2024 for Walter Pennington, who did not last particularly long in that organization. Pennington spent time with Baltimore in 2025. Lorenzen, however, pitched admirably for the Royals after the acquisition, which set up a reunion for 2025 for only 1/$7M guaranteed.
For that low, low price, the Royals got 27 appearances, 26 starts, and 141.2 innings from Biceps. His top-line numbers were…fifth starter adequate. 4.64 ERA / 4.59 FIP / 4.23 xFIP for 1.2 fWAR. If you buy into the price of a win on the market being around $9M, the Royals got surplus value in terms of pure performance/dollar.
But how Lorenzen got there is a little interesting. He had the highest strikeout rate of his career since he was a reliever in 2020. He had the lowest walk rate of his career since 2016. That combination led to the third-best K-BB% of his career, and his absolute best as a starter. He had a roughly league-average BABIP and LOB%, the luck measures I look at.
His problem was the home run ball.
By home run-to-flyball rate (HR/FB), it was not a career high. However, Lorenzen had a career low ground ball rate in 2025, which meant there were just many more fly balls to eventually leave the yard. Honestly, his HR/FB of 14.0% was just too high with a low ground ball rate. If you’re gonna go for fly balls with the Royals stadium and outfield defense…you better limit homers.
That homer rate basically offset his K-BB% improvements to lead to those overall run prevention numbers I cited earlier. They were totally in line with career norms since he returned to starting in 2022 despite the underlying improvement.
Overall, his performance was just a bit worse than a league-average starting pitcher. League-average starting pitchers get paid a lot on the open market. He’s been this guy for the past few years, so teams know what they’re going to get now. The K-BB% improvements are curious, interesting, tempting even, but I’d be worried about that dinger rate.
The Royals declined his mutual option, but could still re-sign him. There’s an opportunity for a reunion if both parties would like, but I think it would need to be in the bullpen.
Lorenzen pumping more gas in the bullpen under this pitching regime is a tantalizing prospect, with the added security that he can step in to start when needed. It’s definitely worth discussing. Does Brian Sweeney think there’s more to squeeze out of those biceps? We’ll see.
