Dodgers Calling Up Hard-Throwing Reliever in Bullpen Shakeup

The former Rockies reliever had a 0.00 ERA at Oklahoma City

Colorado Rockies relief third baseman Ryan McMahon (24) celebrates with pitcher Seth Halvorsen (54) after the game against the Minnesota Twins at Coors Field on July 18, 2025. | IMAGN IMAGES via Reuters Connect

The Los Angeles Dodgers are giving Seth Halvorsen a look, less than a month after they acquired the hard-throwing reliever in a trade with the Colorado Rockies.

Halvorsen, 26, is being activated from his minor league rehab assignment at Triple-A Oklahoma City. He's expected to join the team prior to the Dodgers' series opener against the Kansas City Royals on Monday in Los Angeles, according to Fabian Ardaya of The Athletic.

Dodgers are calling up reliever Seth Halvorsen, sources told The Athletic. The hard-thrower was acquired in a trade with the Colorado Rockies last month.

— Fabian Ardaya (@FabianArdaya) August 10, 2026

Halvorsen, a right-hander, did not allow a run across 6.1 innings with the Dodgers' top farm team after the trade.

Halvorsen was rehabbing a shoulder injury when the Dodgers acquired him from the Rockies for pitcher Nick Frasso and outfielder Landyn Vidourek on July 20.

Halvorsen made his Oklahoma City debut two days later, and threw a scoreless inning in Sacramento.

In his last outing, Thursday in Utah, Halvorsen converted a save by striking out three batters to preserve a 6-3 Comets win.

Halvorsen is known for a 100-mph fastball that was touching 102 at Triple-A. He also throws a slider in the 88-89 mph range.

Seth Halvorsen gets the strikeout on a 101mph fastball 😳 pic.twitter.com/DZjWPFWaxX

— Hyeseong Kim Muse 김혜성 (Fan account) (@HyeseongKimMuse) July 26, 2026

It's a lot like the pitcher the Rockies thought could be a future high-leverage reliever in Denver before the injury.

Halvorsen was a seventh-round pick by the Rockies out of the University of Tennessee in 2023. A multi-inning reliever in college, Halvorsen bypassed the prospect lists entirely and was pitching in the majors 13 months after he was drafted.

In 12 games as a rookie in 2024, Halvorsen went 2-1 with a 1.46 ERA, 13 strikeouts and an 0.81 WHIP in 12.1 innings

Halvorsen made 42 appearances in 2025, his first full season in the majors, recording 11 saves while posting a 4.99 ERA (97 ERA+).

However, Halvorsen missed all of September 2025 dealing with an elbow injury, a harbinger of his lost season to come.

Halvorsen was optioned and recalled from Triple-A Albuquerque three times this season before the Rockies placed him on the injured list July 4 with right shoulder inflammation.

The Dodgers' bullpen has plenty of health issues on its own. Will Klein (elbow), Brock Stewart (shoulder) and Blake Treinen (elbow) would all be pitching in high-leverage roles if healthy. Since they aren't, Halvorsen's return to health is coming at an opportune time.

The transaction, and the corresponding roster move, haven't been officially announced by the team.

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