The Numbers Behind Stroman's Hot Start
04/10/2023 3:17 PM
Article By: Michael Lane
Marcus Stroman (Orleans ‘10/’11) is set to make his third start of the season Wednesday against another former Firebird, Logan Gilbert (Orleans ‘17). In each of his first two starts this season, Stroman went six innings, struck out at least six batters, and didn’t allow a run.
Impressively he did this against the Brewers and Rangers, who rank sixth and eighth respectively in runs scored this season.
While it may be a small sample size, the numbers from Baseball Savant indicate this could be the beginning of an outstanding season for Stroman.
During the 2022 season, Stroman relied primarily on two pitches. He threw his sinker 40.2% of the time and his slurve 23.8% of the time, combining for 64% of his pitches. The remaining 36% of pitches were split amongst his split finger, cutter, four-seam fastball, and slider.
Through his first two starts, Stroman is again relying on those two strong pitches, throwing his sinker 42.5% of the time and his slurve 27.9% of the time.
Notably, Stroman’s average spin rate on both pitches has increased significantly early in the 2023 season.
Stroman’s sinker last year had an average spin rate of 2,265 revolutions per minute (RPM). So far this year, his sinker has an average spin rate of 2,344 RPM, an increase of 79 RPM.
Stroman’s slurve this year has an average spin rate of 2,869 RPM, compared to 2,673 RPM last year, good for an increase of 196 RPM.
Additionally, Stroman has only thrown his slider nine times so far this season, but has seen similar improvements in spin rate. He’s averaging 2,823 RPM on his slider, compared to 2,692 RPM last year, an increase of 131 RPM.
Despite only throwing his slider 5.1% of the time in 2022, it was actually his best put-away pitch, with a PutAway% of 21.4%. The increase in spin rate on his slider could lead to more success striking left-handed batters out over the course of the season.
The increase in spin rates has translated to success in improving his average exit velocity, hard hit rate, barrel percentage, and whiff percentage.
The Cubs impressive infield defense, highlighted by offseason acquisition Dansby Swanson, should also aid Stroman throughout the season.