Brett de Geus Bio
Brett de Geus is an American professional baseball pitcher who was born on November 4, 1997, in Pleasanton, California. He made his Major League Baseball debut in 2021 and has appeared at the top level for several organizations, including the Texas Rangers, Arizona Diamondbacks, Seattle Mariners, Miami Marlins, Toronto Blue Jays, and Philadelphia Phillies. A right-handed reliever, de Geus has spent portions of his career bouncing between the majors and the upper levels of the minors while also taking stints in independent baseball. As of the most recent reporting, he is listed as a free agent.
Early Life and Background
Brett de Geus grew up in Pleasanton, California, and attended Foothill High School, where he played baseball before graduating. After high school, he was not selected in the 2015 Major League Baseball draft, which pushed him toward the college route. He enrolled at Cabrillo College in Aptos, California, to continue his baseball development.
At Cabrillo, de Geus developed into one of the more dependable arms in his conference. As a freshman in 2016, he earned all-conference honors for the Seahawks. He returned as a sophomore in 2017 and produced his strongest college season, going 9-3 with a 1.94 earned run average over 16 games, including 14 starts, which placed him firmly on professional scouting boards.
Path to Professional Baseball
Following his sophomore season at Cabrillo College, de Geus entered the 2017 Major League Baseball draft. The Los Angeles Dodgers selected him in the 33rd round with the 1,000th overall pick. He signed with the Dodgers organization and began his professional career in 2018, pitching for the Ogden Raptors of the Pioneer League.
His stock rose sharply in 2019, when he split the year between the Great Lakes Loons and the Rancho Cucamonga Quakes. Working primarily as a reliever, de Geus went 6-2 with a 1.75 ERA and 72 strikeouts across 61 and two-thirds innings. That fall he was named an Arizona Fall League All-Star, signaling that he was nearing major league consideration before the minor league season was wiped out by the COVID-19 pandemic in 2020.
Brett de Geus Career
Early Career (2018-2020)
de Geus opened his professional career in 2018 with the Ogden Raptors, going 4-5 with a 7.26 ERA over 15 games, including 14 starts. The Dodgers used 2019 to shift him into a relief role, and the move paid off as he delivered a 1.75 ERA across the Great Lakes Loons and Rancho Cucamonga Quakes and earned an Arizona Fall League selection. He was a non-roster invitee to the Dodgers’ 2020 spring training, but the canceled minor league season kept him off the mound for the year.
Texas Rangers and Arizona Diamondbacks (2021-2022)
On December 10, 2020, the Texas Rangers selected de Geus with the second pick in the Rule 5 draft. He made the Rangers’ Opening Day roster in 2021 and made his major league debut on April 1, 2021, allowing three earned runs in one inning. He was designated for assignment on June 23, 2021, after posting an 8.44 ERA over 19 appearances.
The Arizona Diamondbacks claimed him off waivers on June 25, 2021. In 28 relief appearances with Arizona, he went 3-2 with a 6.56 ERA and 15 strikeouts. He was designated for assignment at the end of November and sent outright to Triple-A Reno. In 2022, he struggled to a 5.96 ERA in 17 appearances for Double-A Amarillo and was released by the Diamondbacks organization on June 7, 2022.
Independent Baseball and Royals System (2022-2023)
On June 22, 2022, de Geus signed with the York Revolution of the Atlantic League of Professional Baseball. In 33 games, he went 2-2 with a 6.43 ERA and 31 strikeouts in 35 innings before becoming a free agent. In April 2023 he joined the Frederick Atlantic League team, where he posted a 3.00 ERA in five relief appearances.
On May 11, 2023, the Kansas City Royals purchased his contract and assigned him to Triple-A Omaha. Across 29 appearances split between Omaha and Double-A Northwest Arkansas, he worked to a 4.86 ERA with 36 strikeouts in 46 and one-third innings. He elected free agency on November 6, 2023.
Mariners, Marlins, Blue Jays, and Phillies (2024-2025)
de Geus signed a minor league deal with the Seattle Mariners on December 3, 2023. After three appearances for Triple-A Tacoma, he was selected to the Mariners’ roster on April 8, 2024. He pitched four times for Seattle, allowing one run in three and one-third innings, before being optioned back to Tacoma and later designated for assignment on August 2.
He was claimed off waivers by the Miami Marlins on August 5, 2024, then by the Toronto Blue Jays on September 12, 2024. On January 10, 2025, Toronto designated him for assignment following the signing of Jeff Hoffman. He was traded to the Pittsburgh Pirates for cash on January 15, 2025, claimed by Miami again on February 27, and then claimed by the Philadelphia Phillies on April 1, 2025. His lone Phillies appearance came on May 29 against the Atlanta Braves, when he allowed one run in two innings. He was designated for assignment on July 31 after the Harrison Bader acquisition, sent outright to Triple-A Lehigh Valley, and released on August 17, 2025.
Driving Style and Strengths
de Geus has been used almost exclusively as a relief pitcher at the upper levels, where managers have looked to him to get quick outs and miss bats in short bursts. His best statistical season came in 2019, when he posted a 1.75 ERA and 72 strikeouts across the lower minors, showing the swing-and-miss stuff that once made him an Arizona Fall League All-Star.
Notable Events and Milestones
The signature moment of his major league career came on April 1, 2021, when he made his MLB debut with the Texas Rangers. Other notable beats include being taken with the 1,000th overall pick in the 2017 MLB draft and being selected in the Rule 5 draft by Texas, which carried him onto a major league roster for the first time.
Brett de Geus Career Wins
Through the 2025 MLB season, de Geus had recorded 3 major league wins against 4 losses with a 7.39 ERA and 48 strikeouts. His three MLB victories all came during his 2021 stint with the Arizona Diamondbacks, where he went 3-2 in 28 relief appearances and became a reliable late-inning option for a stretch.
Major League Highlights
His first big league win arrived in 2021 with Arizona, shortly after he had been claimed off waivers from Texas. He appeared in 28 games for the Diamondbacks that season and struck out 15 batters while logging a 3-2 record. He did not register another major league win across his subsequent stops with Seattle, Miami, Toronto, or Philadelphia.
Other Wins and Performances
Outside the majors, de Geus posted a 9-3 record with a 1.94 ERA in his sophomore season at Cabrillo College in 2017. He also went 6-2 with a 1.75 ERA across the Great Lakes Loons and Rancho Cucamonga Quakes in 2019, a season that earned him an Arizona Fall League All-Star nod.
Brett de Geus Family
Family Background and Racing Lineage
Public information about Brett de Geus’s family background is limited. He was raised in Pleasanton, California, and developed into a professional pitcher through the local high school and junior college pathway rather than through a documented baseball family lineage.
Personal Life
Verified details about de Geus’s personal life, including marital status, are not publicly available. He has kept his off-field life largely private while focusing on a professional career that has carried him through more than half a dozen MLB organizations.
2025 Season Performance
de Geus entered 2025 as a member of the Toronto Blue Jays but was designated for assignment on January 10 following the signing of closer Jeff Hoffman. He was traded to Pittsburgh for cash on January 15 and was quickly designated for assignment before being claimed by the Miami Marlins on February 27. He did not make the Marlins’ Opening Day roster and was designated for assignment again on March 30.
The Philadelphia Phillies claimed him on April 1, 2025. He made one appearance for Philadelphia on May 29 against the Atlanta Braves, allowing one run in two innings. He was designated for assignment on July 31 after Philadelphia acquired Harrison Bader, was sent outright to Triple-A Lehigh Valley, and was released by the Phillies organization on August 17, 2025.
Through the 2025 season, his MLB line sat at 3-4 with a 7.39 ERA and 48 strikeouts, reflecting how frequently he has moved between organizations in recent years. With his release from the Phillies, de Geus returned to free agency and was working to find his next opportunity as the offseason progressed.