Bruce Zimmermann Undergoes Core Muscle Surgery

The Orioles announced to reporters, including Roch Kubatko of MASNsports.com, that left-hander Bruce Zimmermann underwent core muscle surgery today. He is expected to be ready for Spring Training.

Zimmermann, 29 in February, has pitched for the O’s in each of the past four seasons, tossing 158 1/3 innings with a 5.57 earned run average. In 2023, he spent most of the season on optional assignment. He made just seven appearances for the big league club, with an ERA of 4.73 in those.

He made 21 starts at the Triple-A level with a 4.42 ERA in 99 2/3 innings. He struck out 24.6% of opponents at that level, walked 8.7% of them and got grounders at a 45% rate. If not for a .377 batting average on balls in play and 67.1% strand rate, his results likely would have been better, which is why his FIP was over a run better than his ERA at 3.25.

The O’s had an excellent season in 2023 but starting pitching still stands out as a target area. Kyle Gibson and Jack Flaherty are both set to become free agents in a couple of weeks, leaving the O’s with Kyle Bradish, Grayson Rodriguez and Dean Kremer in three rotation spots. John Means finished the season with an elbow injury but would be in there if healthy next year. Candidates for rounding out the group include Tyler Wells, DL Hall and Cole Irvin, though Irvin will be out of options next year. Assuming Zimmermann is recovered by the spring as expected, he would be in that mix as well.