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). A starting pitcher, Woo has emerged as one of the most consistent arms in the American League, earning an All-Star selection in 2025 and a place on the All-MLB second team the same year. In only his third major league season, he has developed into a frontline starter whose command and pitch efficiency set him apart across the league.
Early Life and Background
Bryan Joseph Woo was born on January 30, 2000, in Oakland, California, and grew up in the San Francisco Bay Area with his parents and sister. His paternal grandparents were born in China and later moved to California, and Woo visited China twice as a child. As a young fan, he rooted for the San Francisco Giants and admired shortstop Brandon Crawford, reflecting the strong baseball culture of the Bay Area that helped shape his early interest in the sport.
Path to Professional Baseball
Growing up, Woo was primarily an infielder, playing shortstop and third base, and he was not viewed as a pitching prospect until he grew eight inches during high school. He 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) and batted .422 as a switch hitter, earning West Alameda County Conference Foothill Division player of the year honors from the Mercury News. That summer he played for the Peninsula Oilers in the Alaska Baseball League, where the San Francisco Giants attempted to sign him at a scouting event, but he opted to attend college.
Woo enrolled at Cal Poly to play college baseball for the Mustangs, the only program that recruited him as a pitcher rather than as a two-way player. As a freshman in 2019, he posted a 9.13 ERA over 23+2⁄3 innings, and he returned to the Alaska Baseball League that summer, where he was named the league’s top pro prospect. After pitching only 17+2⁄3 innings in a shortened 2020 season cut short by the COVID-19 pandemic, he went 6.11 ERA over 28 innings in 2021 before undergoing Tommy John surgery and missing the rest of the year. He finished his college career with a 4–7 record, one save, a 6.49 ERA, and 89 strikeouts in 69+1⁄3 innings across 31 appearances.
Bryan Woo Career
Minor League Years (2021–2023)
The Seattle Mariners selected Bryan Joseph Woo in the sixth round with the 174th overall pick of the 2021 Major League Baseball draft, and he signed for $318,200, $31,700 above slot value. Still recovering from elbow surgery, he made his professional debut in June 2022 with the Arizona Complex League Mariners, where he was briefly hospitalized after being hit in the face by a line drive but escaped serious injury. He moved quickly through the system, joining the Low-A Modesto Nuts in late June and the High-A Everett AquaSox at the end of July, and posted a 1–4 record with a 4.11 ERA and 84 strikeouts in 57 innings over 16 starts. After the season, he pitched in the Arizona Fall League for the Peoria Javelinas.
Woo began 2023 with the Double-A Arkansas Travelers and excelled, going 3–2 with a 2.05 ERA and 59 strikeouts in 44 innings across nine starts, a stretch during which he began throwing a sinker. His strong performance convinced the Mariners to promote him to the major leagues in early June, setting the stage for his MLB debut.
MLB Debut Season (2023)
On June 2, 2023, the Mariners announced that Woo would be promoted to start the following day against the Texas Rangers, taking Marco Gonzales’ turn in the rotation. His debut was a rough one, as he allowed six runs in two innings, but he settled in over his next few outings. He earned his first major league victory in his fourth start, beating the New York Yankees on June 22, and finished his rookie year with a 4–5 record, a 4.21 ERA, and 92 strikeouts in 87+2⁄3 innings. Mariners manager Scott Servais noted that Woo was still developing his breaking balls as a rookie.
Second MLB Season (2024)
Woo opened 2025 on the injured list with elbow inflammation and did not make his first start until May 10. He quickly emerged as one of the most reliable starters in baseball, posting a 1.07 ERA across his first six starts, the lowest in Mariners history to begin a season. A short stint on the injured list with a hamstring issue interrupted his rhythm, but he returned to anchor the rotation, finishing 2024 with a 9–3 record, a 2.89 ERA, and 101 strikeouts in 121+1⁄3 innings over 21 starts, all improvements from his rookie year. He was the best starting pitcher in MLB at limiting walks, walking only 2.6 percent of batters faced.
All-Star Season (2025)
Woo was one of the most consistent pitchers in baseball in 2025, a season that cemented his place among the American League’s top arms. He was named to the All-Star Game in July, and on July 10 he carried a no-hitter into the eighth inning against the New York Yankees. Before the All-Star break, he ranked third in the AL in strikeout-to-walk ratio and walk rate while piling up more strikeouts than in either of his first two seasons. He set a franchise record by pitching at least six innings in each of his first 25 starts, and he allowed no more than two walks over that stretch, the longest such run to start a season since Cy Young in 1905.
Woo struck out a career-high 13 batters on September 13 in a win over the Los Angeles Angels, but he was removed early from his next start due to a pectoral injury, though he still earned a win over the Houston Astros before the injury ended his regular season. He finished 15–7 with a 2.98 ERA and 198 strikeouts in 186+2⁄3 innings, placing fifth in AL Cy Young Award voting and earning a spot on the All-MLB second team. He ranked in the top five in the AL in wins, ERA, walks plus hits per innings pitched, strikeouts, strikeout-to-walk ratio, and double plays turned, and his four-seam fastball was rated one of the most valuable pitches in the majors by Statcast. He did, however, allow 26 home runs, tied for eighth most in the AL. A pectoral injury kept him off the Mariners roster for the AL Division Series, though he returned to pitch in relief twice in the AL Championship Series, allowing three runs, four hits, and three walks while striking out two in 4+1⁄3 innings of his first postseason.
Driving Style and Strengths
Bryan Joseph Woo relies primarily on a four-seam fastball and sinker that both average 95 miles per hour, leaning on those pitches nearly 75 percent of the time, a higher share than most contemporary starters. He complements the fastball pair with a changeup and a slider, some of which are classified as a sweeper, and he throws an unusually high percentage of strikes that limits free passes. He works from a low arm slot with a low release point and a smooth delivery, a profile that makes it difficult for hitters to square up his pitches and helps explain his elite command metrics.
Notable Events and Milestones
Woo’s signature moments include his first major league win against the New York Yankees on June 22, 2023, the 1.07 ERA he posted across his first six starts of 2024, and his All-Star selection and near no-hitter against the Yankees in 2025. His 25-start streak of at least six innings set a Seattle franchise record, and his 13-strikeout performance against the Los Angeles Angels on September 13, 2025, marked a new career high.
Bryan Woo Career Wins
Bryan Joseph Woo has built his win totals in stages, beginning with a strong run through the Mariners’ minor league system before establishing himself in the major leagues. He has notched his first MLB victory against the New York Yankees and has added key wins in each of his three big league seasons, including standout performances against the Los Angeles Angels and the Houston Astros in 2025.
MLB Highlights
In his rookie season, Woo went 4–5 with a 4.21 ERA, with his first MLB win coming against the New York Yankees on June 22, 2023. He improved markedly in 2024, going 9–3 with a 2.89 ERA over 21 starts, the most wins and lowest ERA of his career at that point. In 2025, he went 15–7 with a 2.98 ERA, finishing fifth in AL Cy Young Award voting and earning All-MLB second team honors.
Other Wins and Performances
Woo went 3–2 with a 2.05 ERA across nine starts for the Double-A Arkansas Travelers in 2023, and he went 1–4 with a 4.11 ERA and 84 strikeouts in 57 innings across three minor league levels in 2022, all while returning from Tommy John surgery.
Bryan Woo Family
Family Background and Racing Lineage
Bryan Joseph Woo grew up in the San Francisco Bay Area with his parents and his sister. His paternal grandparents were born in China and later moved to California, giving him a mixed cultural heritage that he has acknowledged through childhood visits to China.
Personal Life
Woo has kept most of his personal life out of the public eye, and limited verified information is available about his relationships. His parents are known to attend most of his MLB starts, and he has carried a connection to his Oakland roots throughout his career, including a 2024 distinction as the last person born in Oakland to play an MLB game in Oakland. He has also been known to wear custom cleats featuring illustrations of professional wrestler Ric Flair, a tribute tied to his surname.
2025 Season Performance
Bryan Joseph Woo put together one of the most consistent seasons of any American League starter in 2025, going 15–7 with a 2.98 ERA and 198 strikeouts in 186+2⁄3 innings. He ranked in the top five in the AL in wins, ERA, walks plus hits per innings pitched, strikeouts, strikeout-to-walk ratio, and double plays turned, while his four-seam fastball was rated among the most valuable in baseball by Statcast. He paced the league with a franchise-record 25 consecutive starts of at least six innings to open the year, and he was named to both the All-Star Game and the All-MLB second team.
His season ended on a difficult note when a pectoral injury forced him out of his final regular season start and kept him off the Mariners roster for the AL Division Series, though he returned in relief during the AL Championship Series. He finished fifth in AL Cy Young Award voting despite the late injury, underscoring how dominant his work was across more than 30 starts. With his health expected to return and his command still elite, Bryan Joseph Woo enters the offseason positioned as a clear frontline starter for the Seattle Mariners.