Bryan Woo Bio
Bryan Joseph Woo (born January 30, 2000) is an American professional baseball pitcher for the Seattle Mariners of Major League Baseball (MLB). He made his MLB debut in 2023. In 2025, he was named to the All-Star Game and All-MLB Second Team, establishing himself as one of the most consistent pitchers in baseball. Woo was born in Oakland, California, and grew up in the San Francisco Bay Area.
Early Life and Background
Woo was born in Oakland, California, to a Caucasian American mother and an Asian American father of Chinese descent. He grew up in the San Francisco Bay Area with his parents and sister. As a child, he was a fan of the San Francisco Giants, with Brandon Crawford as his favorite player. His paternal grandparents were born in China and moved to California, and Woo visited China twice as a child.
Growing up, Woo primarily played shortstop and third base. He was not viewed as a pitching prospect until he grew eight inches during high school. Woo attended Alameda High School in Alameda, California, and did not pitch regularly until his junior year. As a senior in 2018, he went 8-2 with a 1.25 earned run average (ERA) while batting .422 as a switch hitter. He was named the player of the year in the West Alameda County Conference Foothill Division by the Mercury News. That summer, he played for the Peninsula Oilers in the Alaska Baseball League. The San Francisco Giants attempted to sign Woo at a scouting event in Alaska, but he chose to attend college instead.
Path to Professional Baseball
Woo enrolled at Cal Poly to play college baseball for the Mustangs. He chose Cal Poly primarily due to its academic reputation and because it was the only program that recruited him as a pitcher rather than a two-way player. As a freshman in 2019, he struggled with a 9.13 ERA over 23 2/3 innings. He returned to play for the Peninsula Oilers that summer and was named the league’s top pro prospect. He pitched only 17 2/3 innings as a reliever in 2020 before the season was canceled due to the COVID-19 pandemic.
In 2021, Woo had a 6.11 ERA over 28 innings before undergoing Tommy John surgery, which ended his season. He started six of the 31 games he pitched in college, finishing with a 4-7 win-loss record, one save, a 6.49 ERA, and 89 strikeouts in 69 1/3 innings.
Bryan Woo Career
Early Career (2021–2023)
The Seattle Mariners selected Woo in the sixth round with the 174th overall selection of the 2021 MLB Draft. He signed for $318,200. Still recovering from elbow surgery, he made his professional debut in June 2022 with the Arizona Complex League Mariners. In one game, he was rushed to the hospital after being hit in the face by a line drive but was not seriously injured. He was promoted to the Low-A Modesto Nuts in late June, then the High-A Everett AquaSox at the end of July. Over 16 starts for the three clubs, Woo posted a 1-4 record with a 4.11 ERA and 84 strikeouts in 57 innings.
Seattle Mariners Breakthrough (2023)
Woo started 2023 with the Double-A Arkansas Travelers. In nine starts, he had a 3-2 record and 2.05 ERA with 59 strikeouts in 44 innings pitched. On June 2, 2023, the Mariners announced that Woo would be promoted to the major leagues to start the following day against the Texas Rangers. Starting in place of Marco Gonzales, Woo had a rough debut, allowing six runs in two innings. He won his first MLB game in his fourth start, defeating the New York Yankees on June 22. He finished his rookie season with a 4-5 record, 4.21 ERA, and 92 strikeouts in 87 2/3 innings.
Seattle Mariners Era (2024–Present)
Despite several injuries, Woo improved significantly in 2024. He began the season on the injured list with elbow inflammation. He made his first start on May 10. In his first six starts, he posted a 1.07 ERA, the lowest in Mariners history to begin a season. He was scratched from his next start on June 11 and made two more starts, earning losses in both, before returning to the injured list on June 25 with a hamstring injury. He was activated on July 12. He ended 2024 with a 9-3 record and 2.89 ERA, striking out 101 batters in 121 1/3 innings over 21 starts. He was the best MLB starting pitcher at avoiding base on balls, walking just 2.6 percent of batters faced.
Woo was one of the most consistent pitchers in 2025. He was named to the All-Star Game in July. On July 10, he carried a no-hitter into the 8th inning against the Yankees. Before the All-Star break, he ranked third in the American League (AL) in strikeout-to-walk ratio and walk rate. Woo pitched at least 6 innings in his first 25 starts, a franchise record. During that stretch, he also allowed no more than two walks, the longest such streak to start a season since Cy Young in 1905. That consistent length benefited the Mariners’ bullpen. Woo struck out a career-high 13 batters on September 13 in a win over the Los Angeles Angels. He was removed early from his next start due to a pectoral injury but earned a win over the Houston Astros to end his regular season. He finished 15-7 with a 2.98 ERA and 198 strikeouts in 186 2/3 innings. He finished fifth in AL Cy Young Award voting and was named to the All-MLB Second Team. His fastball was one of the most valuable pitches in the majors, and he had the best command in baseball, according to PitchingBot analytics.
Notable Events and Milestones
Woo’s pectoral injury kept him off the Mariners roster for the AL Division Series but he pitched in relief twice in the AL Championship Series. In the decisive Game 7, he allowed two runners on and was relieved by Eduard Bazardo, who allowed a series-winning three-run home run, with two runs charged to Woo. In his first postseason, he allowed 3 runs, 4 hits, and 3 walks while striking out 2 in 4 1/3 innings. In 2026, Woo declined an invitation to pitch for the United States national team in the World Baseball Classic, citing his increased workload in 2025.
Bryan Woo Career Wins
Through June 18, 2026, Woo has compiled a 34-20 win-loss record with a 3.34 ERA and 480 strikeouts across his MLB career. His career highlights include his first MLB win against the New York Yankees in June 2023, his All-Star selection and All-MLB Second Team honors in 2025, and his fifth-place finish in AL Cy Young Award voting that same year.
Seattle Mariners Highlights
Woo’s breakthrough season came in 2025 when he went 15-7 with a 2.98 ERA and 198 strikeouts. He set a Mariners franchise record with 25 starts of at least 6 innings pitched. His 198 strikeouts that season surpassed his combined total from his first two MLB seasons. His career-high 13 strikeouts came on September 13, 2025, against the Los Angeles Angels. In 2024, he posted a 9-3 record with a 2.89 ERA in 21 starts, and his 1.07 ERA through his first six starts marked the best beginning to a season in Mariners history.
Bryan Woo Family
Family Background and Personal Life
Woo was born in Oakland, California, to a Caucasian American mother and an Asian American father of Chinese descent. His paternal grandparents were born in China and relocated to California. Woo visited China twice as a child. He grew up in the San Francisco Bay Area with his parents and sister. His parents attend all his MLB starts. In 2024, Woo became the last person born in Oakland to play an MLB game in Oakland. During a 2024 start, Woo wore custom cleats with illustrations of professional wrestler Ric Flair, who was known for yelling “woo.”
2025 Season Performance
The 2025 season marked Woo’s emergence as one of baseball’s premier pitchers. After an injury-shortened 2024 campaign, he returned with remarkable consistency. He was named to the All-Star Game in July and earned All-MLB Second Team recognition. His 25 consecutive starts of at least 6 innings set a new Mariners franchise record, and his ability to limit walks made him invaluable to Seattle’s pitching staff. His fastball ranked among the most valuable pitches in the majors, and analytics systems rated his command as the best in baseball. Despite a pectoral injury that ended his regular season, he placed fifth in AL Cy Young Award voting and helped the Mariners advance to the AL Championship Series, where he pitched in relief during Game 7. His 2025 performance established him as a cornerstone of Seattle’s rotation for years to come.