Seth Martinez Bio
Seth Antonio Martinez is an American professional baseball pitcher and free agent. A native of Sierra Vista, Arizona, Martinez advanced from a successful college career at Arizona State University to a professional path that began after he was selected in the 17th round of the 2016 Major League Baseball draft by the Oakland Athletics. He reached the major leagues in 2021 after being picked in the minor league phase of the 2020 Rule 5 draft by the Houston Astros and has since worked primarily as a relief pitcher in MLB.
Early Life and Background
Seth Antonio Martinez was born on August 29, 1994, in Sierra Vista, Arizona, and grew up in the Phoenix area. He attended Sunrise Mountain High School in Peoria, Arizona, where he played baseball and golf and compiled a strong high-school pitching record, including a junior-year no-hitter and statewide recognition. His father, Bobby Martinez, was a high-school baseball coach, and his mother is Kelly Martinez; he also has a sister, Taylor.
Martinez matriculated to Arizona State University and joined the Arizona State Sun Devils baseball program. He developed as both a starter and reliever in college, demonstrating strikeout ability and durability across multiple seasons. As a junior in 2016 he posted a 9–4 record with a 2.75 earned run average and 94 strikeouts in more than 111 innings, earning first-team All-Pac-12 honors and second-team All-American recognition from Louisville Slugger.
Path to Baseball
Martinez’s performance at Arizona State positioned him for professional opportunity when the Oakland Athletics selected him in the 17th round of the 2016 MLB draft. He began his pro career in the Athletics’ system with brief assignments in the Arizona League and Low-A and moved through Single-A and High-A levels while converting to a full-time relief role in 2018. That season he led his Single-A team with 15 saves, a sign that his role would shift toward late-inning relief work.
After solid progression through the Athletics’ minor league ranks and a strong 2019 showing across High-A and Double-A, Martinez lost the 2020 minor-league season to the pandemic but remained on the radar of other organizations. The Houston Astros selected him in the minor league phase of the 2020 Rule 5 draft, providing a route to major-league opportunities that culminated in a 2021 big-league debut.
Seth Martinez Career
Early Career (2016–2020)
Martinez signed with the Oakland Athletics after the 2016 draft and began his professional career in their lower-level affiliates. He pitched briefly in the Arizona League before earning promotions to the Vermont Lake Monsters and the Beloit Snappers, where he compiled innings as a starter and then as a reliever. Across 2017 and 2018 he built experience and adjusted to a relief workload, posting strong strikeout totals and converting to a primary late-inning role.
In 2019 Martinez advanced to High-A Stockton and Double-A Midland, showing improved strikeout rates and effectiveness against higher-level hitters. The cancellation of the 2020 minor league season halted competitive action that year, but his work to that point set the stage for a Rule 5 minor-league phase selection by the Houston Astros in December 2020.
Houston Astros Breakthrough (2021–2024)
The Houston Astros assigned Martinez to Triple-A Sugar Land to start 2021 and called him up for his major-league debut on September 20, 2021, when he threw a scoreless ninth inning. He closed his 2021 cup-of-coffee with mixed results but established himself as a left-handed relief option in the organization. In 2022 Martinez spent time between Houston and Sugar Land, working primarily as a long reliever and posting a 2.09 ERA across 29 major-league appearances that season while recording his first MLB win on September 15, 2022.
Martinez continued to split time between the majors and Triple-A in 2023, recording his first major-league save on June 25, 2023, and throwing multiple multi-inning relief outings. In 2024 he appeared in a career-high 44 games for the Astros, compiling a 3–2 record, one save, a 3.59 ERA and a career-best 52 2/3 innings pitched while also making several appearances back with Sugar Land, where he maintained a low ERA.
Miami Marlins Season (2025)
Martinez’s 2025 campaign included a period of roster movement before he reached the Miami Marlins organization. After a sequence of waiver claims and designations, he cleared waivers and spent time with the Triple-A Jacksonville Jumbo Shrimp, where he made 41 appearances and recorded a 3–2 record with a 3.71 ERA, 54 strikeouts and eight saves in roughly 43 2/3 innings. The Marlins selected his contract on August 27, 2025, adding him to the major-league roster for six appearances, during which he recorded a 5.40 ERA across 6 2/3 innings. He was designated for assignment on September 11, 2025, and elected free agency after clearing waivers on September 13.
Free Agent Era (2025–Present)
Following the 2025 season, Seth Martinez entered free agency. As a left-handed pitcher with major-league experience, Martinez presents a relief option for clubs seeking multi-inning bullpen depth. His professional history includes starter-to-reliever transition, consistent strikeout ability in the minors, and demonstrated capacity to handle long relief and late-inning situations in the majors.
Pitching Style and Strengths
Martinez profiles as a southpaw reliever who combines multiple pitches to generate strikeouts and induce soft contact. His strengths include the ability to work multiple innings in relief, a history of low walk and WHIP figures in productive minor-league seasons, and experience stepping into varied bullpen roles from long relief to late-inning holds. Those traits have allowed him to adapt to roster changes and contribute when called up.
Notable Events and Milestones
Key moments in Martinez’s career include his MLB debut for the Houston Astros on September 20, 2021, his first major-league win on September 15, 2022, and his first MLB save on June 25, 2023. He was part of the Astros organization during playoff-caliber seasons and has compiled a body of work across Triple-A and MLB that includes late-inning saves and multi-inning relief outings.
Seth Martinez Career Wins
Across his major-league appearances through the 2025 season, Martinez registered a 6–6 win–loss record with a 4.00 earned run average and 126 strikeouts. Those totals reflect his accumulated work across stints with the Houston Astros and the Miami Marlins as well as sustained innings in Triple-A affiliates where he served both as a setup option and occasional closer.
MLB Highlights
Martinez’s MLB highlights include his scoreless MLB debut in late 2021, a string of scoreless long-relief innings to open his 2022 season, and a first major-league save in 2023 against the Los Angeles Dodgers. His 2024 season with the Astros represented a career high in appearances and innings pitched at the major-league level, underlining his development as a reliable bullpen piece.
Other Wins & Perfromances
In the minor leagues Martinez compiled seasons featuring high strikeout totals and save totals, including a 2018 campaign in which he led his Single-A club with 15 saves. His Triple-A results in multiple seasons showcased low ERAs and the ability to close games, which supported multiple major-league callups and roster opportunities.
Seth Martinez Family
Family Background and Racing Lineage
Martinez comes from a baseball-supportive family in Arizona. His father, Bobby Martinez, worked as a high-school baseball coach and aided his early development, while his mother, Kelly Martinez, and sister Taylor were part of his local support network through high school and collegiate competition.
Personal Life
Public details on Martinez’s personal life focus on his family background and amateur roots. There are no widely reported public records of a spouse or children in available verified sources through the 2025 season.
2025 Season Performance
The 2025 season was defined by roster movement and productive Triple-A work for Martinez. After a series of waiver claims and designations early in the year, he settled with the Miami Marlins organization at Triple-A Jacksonville, where he posted a 3.71 ERA with eight saves and 54 strikeouts in 41 appearances, prompting a late-August promotion. His short MLB stint featured six appearances and a 5.40 ERA, after which he was designated for assignment and elected free agency in mid-September. That 2025 timeline left Martinez as a free agent with recent proven Triple-A closing experience and multiple years of MLB relief innings on his résumé.