Ryan Zeferjahn

Ryan Joseph Zeferjahn ( ; born February 28, 1998) is an American professional baseball pitcher for the Chicago Cubs of Major League Baseball (MLB). He has previously played in MLB for the Los Angeles Angels.

Amateur career A native of Topeka, Kansas, Zeferjahn played college baseball at the University of Kansas. In 2017, he played collegiate summer baseball with the Falmouth Commodores of the Cape Cod Baseball League. Professional career Boston Red Sox The Boston Red Sox selected Zeferjahn in the third round, with the 107th overall selection, of the 2019 Major League Baseball draft. He made his professional debut with the Low–A Lowell Spinners, logging a 4.50 ERA in 12 starts. Zeferjahn did not play in a game in 2020 due to the cancellation of the minor league season because of the COVID-19 pandemic.

Zeferjahn returned to action in 2021 with the rookie–level Florida Complex League Red Sox and Single–A Salem Red Sox. In 16 starts between the two affiliates, he compiled a 1–4 record and 5.98 ERA with 59 strikeouts across innings pitched. Zeferjahn split the 2022 campaign between the High–A Greenville Drive and Double–A Portland Sea Dogs. In 34 appearances pitching mainly in relief, he accumulated a 5–4 record and 5.05 ERA with 80 strikeouts over innings pitched.

Zeferjahn spent 2023 with Portland, also making two scoreless outings for Salem. In 34 appearances out of the bullpen for Portland, he recorded a 5.02 ERA with 68 strikeouts across 43 innings of work. Zeferjahn began the 2024 season with Portland, and was promoted to the Triple–A Worcester Red Sox after seven scoreless appearances. In 18 games for Worcester, he registered a 5.47 ERA with 31 strikeouts and 4 saves over innings.

Los Angeles Angels On July 30, 2024, Zeferjahn, Matthew Lugo, Yeferson Vargas, and Niko Kavadas were traded to the Los Angeles Angels in exchange for Luis García. In five games for the Triple–A Salt Lake Bees, he posted a 2.35 ERA with 8 strikeouts. On August 23, Zeferjahn was selected to the 40-man roster and promoted to the major leagues for the first time. In 12 appearances for Los Angeles during his rookie campaign, Zeferjahn recorded a 2.12 ERA with 18 strikeouts over 17 innings of work.

On April 6, 2025, Zeferjahn recorded his first career win after tossing a scoreless sixth inning against the Cleveland Guardians.

Chicago Cubs On August 3, 2026, the Angels traded Zeferjahn to the Chicago Cubs in exchange for Moises Ballesteros and Mason McGwire.