The Colorado Rockies' newest pitcher showed promise in his first Major League Baseball game.
It didn't last long, but Sean Sullivan's Major League Baseball debut gave Colorado Rockies fans plenty of optimism about what's to come.
The former Northwestern pitcher threw three scoreless innings to start the Rockies' 6-4 loss to the Athletics on Friday night. Sullivan struck out two batters and gave up just two hits before leaving the game due to an illness.
"He’s fine now, but he was sick as a dog, throwing up in the bullpen before the game," Colorado manager Warren Schaeffer told MLB.com. "He grinded for us today in his big-league debut. I don't know how much of that he's going to remember, coming in between innings and throwing up."
Across 49 pitches, Sullivan threw 33 strikes and 16 balls. He struck out Athletics batters Colby Thomas and Zack Gelof swinging.
The Rockies are now 26-44 through 70 games, the worst winning percentage in the Majors.
Sullivan was the No. 11-ranked prospect in Colorado's farm system. Red Sox right-handed pitcher Tyler Uberstine (No. 13) is the only other former Northwestern player ranked in MLB Pipeline's top 30 for any team.
Jun 12, 2026; Summerlin, Nevada, USA; Colorado Rockies pitcher Sean Sullivan (45) throws the ball during the first inning against the Athletics at the Las Vegas Ballpark. Mandatory Credit: Lucas Peltier-Imagn ImagesSeveral other ex-Wildcats are currently playing baseball in the minors, though most did not finish their collegiate careers in Evanston. Miami Marlins CF Ethan O'Donnell (Triple-A), Marlins INF Jay Beshears (Double-A), Cincinnati Reds C Michael Trautwein (Double-A), Detroit Tigers OF Stephen Hrustich (Rookie Affiliate Rehab) and New York Yankees RHP Ben Grable (Double-A) are all working their way through their respective farm systems. Only Trautwein was drafted directly from Northwestern.
Sullivan played just one campaign for the 'Cats, his true freshman season in 2022. The Andover, Mass., native started 13 games, went 5-2 with a 4.45 ERA and struck out 78 batters. Northwestern went just 24-27, leading Sullivan to transfer to Wake Forest.
As a core member of the Demon Deacons' pitching staff, Sullivan earned First Team All-ACC and Second Team All-American honors. Wake Forest reached the semifinals of the Men's College World Series and Sullivan put himself on the map for MLB teams.
The Rockies selected Sullivan with the No. 46 overall pick in the 2023 MLB Draft, and he rose quickly through Colorado's farm system. Prior to being called up, Sullivan started 11 games with Triple-A Albuquerque this season, in which he compiled 50 strikeouts, went 5-3 and logged a 5.60 ERA.
Once Sullivan recovers from his illness, he'll look to provide hope to a young Rockies core in the midst of a rebuild.
