Ranking the Rockies: No. 15, Seth Halvorsen

The hard-throwing righty gave hope for the future of the bullpen after a meteoric rise through the farm system.

Welcome to the 2024 edition of Ranking the Rockies, where we take a look back at every player to log playing time for the Rockies in 2024. The purpose of this list is to provide a snapshot of the player in context. The “Ranking” is an organizing principle that’s drawn from Baseball Reference’s WAR (rWAR). It’s not something the staff debated. We’ll begin with the player with the lowest rWAR and end up with the player with the highest.

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No. 15, Seth Halvorsen: 0.6 rWAR

Right-handed pitcher Seth Halvorsen might have been the second pitcher the Colorado Rockies drafted out of the University of Tennessee in 2023, but he became the first to break into the big leagues when he made his major league debut at the tail end of the 2024 season.

The seventh round draft pick had a meteoric rise through the Rockies’ minor league system, making his way from the Arizona Complex League Rockies all the way to the Double-A Hartford Yard Goats in 2023 while skipping Low-A ball entirely. His ability to strike out batters was on full display as he tallied 13 strikeouts in 13 appearances over 13 ¹⁄₃ innings of work.

His rise continued in 2024, though he spent the bulk of the season in Double-A. He struck out 41 batters and had a 4.84 ERA over 35 ¹⁄₃ innings before being promoted to Triple-A in August. While playing for the Albuquerque Isotopes in the Pacific Coast League—a notoriously difficult task for pitchers—Halvorsen rose to the occasion. He struck out 15 batters in nine innings while giving up just three earned runs. Halvorsen also had multiple strikeouts in seven of his nine Triple-A appearances.

The Rockies summoned Seth Halvorsen to Coors Field to make his big league debut against the playoff-bound Baltimore Orioles. With two outs and runners on base, he took the mound on August 30th and threw his first major league pitch: a four seam fastball at 100 MPH, showcasing his effortless velocity. That one pitch was all he needed to end the inning.

Halvorsen was another breath of fresh air in the Rockies’ once-beleaguered 2024 bullpen as he joined fellow rookies Victor Vodnik, Angel Chivilli, and Luis Peralta as part of the team’s youth movement.

Described by the Rockies’ development staff as “confrontationally matter-of-fact and very confident,” Halvorsen faced the challenge of coming out of the Rockies’ bullpen head-on.

“No, I don’t think so,” Halvorsen told Purple Row when asked if he felt any extra pressure after his quick ascent to the majors. “I’m just taking it day by day and pitch by pitch, and I’m just grateful to be out here.”

And day by day, pitch by pitch, Halvorsen was excellent on the mound for the Rockies. He started his big league career with nine straight scoreless appearances over 9 ²⁄₃ innings. During that time he gave up just two walks to nine strikeouts and only allowed five hits. He didn’t even give up his first two big league walks until that ninth appearance—where he earned his first career save against the juggernaut Los Angeles Dodgers at Chavez Ravine.

It was against those same Dodgers where Halvorsen hit his first bump. On September 22nd—the day after that first career save—Halvorsen was called to the mound in the bottom of the ninth inning to do it again. Two of the league’s best players in Shohei Ohtani and Mookie Betts took him deep in back-to-back at-bats for the walk-off for Halvorsen’s first career loss.

Those two earned runs would be the only ones Halvorsen yielded during his time with the big league club. He would even get one more shot to face the Dodgers in the Rockies’ season finale, where he pitched 1 ²⁄₃ scoreless, hitless innings and struck out three batters.

Halvorsen finished the season with a 1.46 ERA in 12 appearances and 12 ¹⁄₃ innings. During that time he allowed just those two earned runs on eight hits and earned two saves. He showcased his excellent command by dialing up 13 strikeouts while walking only two batters of the 46 he faced. All the while sitting in baseball’s top percentile for fastball velocity, averaging 99.9 MPH on his four seam fastball and 100.1 MPH on his sinker per Statcast.

24-year-old Seth Halvorsen has the potential to be a key player in the Rockies’ young bullpen in 2025 that could be a critical part of the team’s rebuild. For his part, Halvorsen is grateful.

“Everybody here is a great player, and so I’m just excited to play with everybody here. It’s been amazing. It’s been an amazing experience, an amazing journey, playing baseball. And yeah, just… just grateful to be able to play for the Rockies.”