By refining his arsenal in Chicago’s renowned pitching lab, Ryan Rolison has transformed from a twice-designated castoff into a lights-out reliever fueling the Cubs' early-season success.
The Chicago Cubs are no strangers to developing pitchers.
Just look at all the pitchers that had career years in their first season with the Cubs in 2025. Brad Keller posted a career-best 2.07 ERA, Drew Pomeranz finished with a 2.17 ERA in his first Major League season since 2021, and Chris Flexen even turned into a quality reliever with a 3.08 ERA.
Now, another first-year Cubs reliever has benefited from Chicago’s pitching lab.
Left-handed reliever Ryan Rolison has been lights out for the Cubs' bullpen since being called up on April 14. Rolison has a 3.12 ERA and 10 strikeouts across 8 ⅔ innings pitched so far this season.
He also played a big role in both of the team’s recent walk-off wins against the Reds. The southpaw struck out the side in the ninth inning of Monday’s game to keep the score at 4-3 and then threw another scoreless inning with one walk and two strikeouts in the 10th inning before Michael Busch walked it off in the bottom frame.
Rolison is really starting to emerge as a key arm in Chicago’s bullpen. He has allowed no runs in five of his six appearances and continues to throw the ball well in different situations.
It’s not easy coming into a game with a runner already on second base in extra innings. But Rolison made quick work in his relief appearance on Tuesday by striking out the first two batters he faced and getting Elly De La Cruz to ground out to end the inning.
So, what’s allowed Rolison to thrive in the early going?
This is the same pitcher who really struggled in his rookie season (7.02 ERA across 42 ⅓ innings) and was designated for assignment by the Colorado Rockies, Atlanta Braves, and Chicago White Sox this past offseason.
Here’s what Rolison had to say about his improved numbers to start the season.
“[The Cubs] brought me in, showed me a couple pitches I can throw, improved my arsenal,” he told reporters.
The Cubs are notorious for adjusting pitchers’ arsenals to get the most out of them. That’s exactly what they have done with Rolison.
The 28-year-old has added both a sweeper and a sinker to his arsenal. That sweeper has been a difference maker for him against left-handed batters, as he has a 75% whiff rate and a 25% putaway rate on that pitch so far.
By adding those two pitches, Rolison is becoming a more well-rounded pitcher. He now has six pitches that he can throw to keep hitters off balance (four-seam fastball, curveball, slider, sweeper, changeup, and sinker).
Those six pitches have collectively helped Rolison take that next step. The left-hander has an expected 2.52 ERA, a .206 batting average against, a 31.3% strikeout rate, a 6.3% walk rate, and a 5% barrel rate to start his Cubs career.
The Cubs might have gotten a steal in Rolison.