Seth Halvorsen
Seth Michael Halvorsen is an American professional baseball pitcher for the Colorado Rockies of Major League Baseball.
Amateur career
Halvorsen grew up in Plymouth, Minnesota and attended Heritage [Christian Academy |Heritage Christian Academy] in Maple Grove, Minnesota. He was the Minnesota Gatorade [Player of the Year awards|Gatorade Player of the Year] and a Rawlings high school All-American in 2018. He was a two-way player and threw a 16-strikeout shutout while hitting two home runs in the 1A state championship game. He was selected in the 30th round of the 2018 MLB draft by the Minnesota Twins but did not sign.Halvorsen then played college baseball at the University of Missouri. After appearing in 4 games in 2019, he was shut down and had Tommy John surgery. He returned in 2020 as a center fielder, playing in 14 games. He resumed pitching in 2021 and led the Tigers baseball|Tigers] with 4 wins, 70 strikeouts, and 72 innings pitched. That summer, the Philadelphia Phillies selected him in the 19th round of the 2021 [Major League Baseball draft|2021 MLB draft]. He did not sign. He played collegiate summer baseball with the Hyannis Harbor Hawks of the Cape Cod Baseball League.
Halvorsen then transferred to play for the Tennessee Volunteers but missed all of 2022 after fracturing his elbow. He returned as a reliever in 2023, going 3–3 with 2 saves, a 3.81 ERA and 52 strikeouts in 52 innings.
Professional career
Halvorsen was selected by the Colorado Rockies in the seventh round of the 2023 MLB draft and signed. He split his first professional season between the rookie-level Arizona Complex League Rockies, High+A Spokane Indians, and Double-A Hartford Yard Goats. In 13 appearances for the three affiliates, he had a 2–0 record, 2.70 ERA, and 13 strikeouts across innings pitched.Halvorsen began the 2024 season in Double-A and earned a promotion to the Triple-A Albuquerque Isotopes in early August. In 41 minor league appearances out of the bullpen, he had a 5–2 record, 4.47 ERA, and 56 strikeouts in innings pitched.
On August 30, Halvorsen was addedd to the 40-man roster and promoted to the major leagues for the first time. That night, he became the first Rockies pitcher to throw only one pitch and get an out in his MLB debut, inducing a Gunnar Henderson groundout. He earned his first win on September 12 against the Detroit Tigers. On September 21, he earned his first career save, tossing a scoreless inning against the Los Angeles Dodgers. He ended his first MLB season with a 2–1 record, two saves, and a 1.46 ERA.
Halvorsen threw a 103.3 miles-per-hour fastball on July 3, 2025, the fastest pitch by a Colorado pitcher since at least 2015. His fastball averaged 100 miles per hour, the third fastest of any major league pitcher who faced at least 100 batters. He was 1–2 with 11 saves in 42 games in his rookie season with Colorado. His season ended in early August after he went on the injured list with a right elbow strain.