Isaac Mattson Bio
Isaac Gerald Mattson (born July 14, 1995) is an American professional baseball pitcher for the Pittsburgh Pirates of Major League Baseball (MLB). He has previously played in MLB for the Baltimore Orioles. Mattson attended Harbor Creek High School in Harborcreek, Pennsylvania, where he played both baseball and basketball before continuing his career at the University of Pittsburgh. Since being drafted by the Los Angeles Angels in 2017, he has played for multiple organizations, working his way through the minors before reaching the major leagues.
Early Life and Background
Isaac Gerald Mattson was born on July 14, 1995, in Harborcreek, Pennsylvania. He is the son of Edward and Debra Mattson, and he was raised alongside seven siblings in a close family. Growing up in the Harborcreek area, Mattson developed an early interest in athletics, playing both baseball and basketball during his school years. His multi-sport background helped him build the versatility and competitive habits that would later shape his pitching career.
Mattson attended Harbor Creek High School, where he starred in both baseball and basketball. During his senior year in 2014, he posted an outstanding 6–0 record on the mound with a 0.67 ERA while also batting .531, drawing attention from college and professional scouts. Despite his strong senior season, Mattson was not selected in the 2014 Major League Baseball draft. He chose to continue his baseball career at the University of Pittsburgh, beginning the next chapter of his development.
Path to Professional Baseball
At the University of Pittsburgh, Mattson gradually built a reputation as a reliable relief pitcher. As a freshman in 2015, he appeared in 22 games, going 1–1 with a 3.82 ERA. He returned for his sophomore season in 2016, when he worked 34 innings in relief and posted a 2–0 record with a 3.71 ERA. After his sophomore year, Mattson gained valuable summer experience with the Chatham Anglers of the Cape Cod Baseball League, where he was named an all-star.
In 2017, his junior year, Mattson continued to perform well out of the bullpen, pitching 31 innings and going 1–0 with a 2.87 ERA while striking out 41 batters. His consistency across three college seasons convinced the Los Angeles Angels to select him in the 19th round of the 2017 Major League Baseball draft, launching his professional career.
Isaac Mattson Career
Early Career (2017–2019)
After signing with the Los Angeles Angels, Mattson began his professional journey in the lower levels of the minor leagues. He made his debut with the Arizona League Angels before being promoted to the Orem Owlz, where he earned All-Star honors. Across 31 and a third innings between the two clubs, he went 1–0 with a 1.44 ERA, signaling his early potential as a relief pitcher.
In 2018, Mattson split the season between the Burlington Bees and the Inland Empire 66ers, going 7–4 with a 3.82 ERA in 25 games, including 11 starts. The following year, he began with the 66ers before earning a midseason promotion to the Mobile BayBears in May and later to the Salt Lake Bees. Over 37 relief appearances across three clubs in 2019, he posted a 6–3 record with a 2.33 ERA, striking out 110 batters in 73 and a third innings. His strong 2019 campaign earned him a selection to the Arizona Fall League, where he suited up for the Mesa Solar Sox.
Baltimore Orioles Era (2019–2022)
On December 4, 2019, Mattson was traded to the Baltimore Orioles as part of the deal that sent Dylan Bundy to the Los Angeles Angels. He did not appear in a minor league game in 2020 because the minor league season was canceled due to the COVID-19 pandemic. On November 20, 2020, the Orioles added him to their 40-man roster, and on May 3, 2021, he was promoted to the major leagues for the first time.
Mattson made his major league debut on May 7, 2021, pitching two-thirds of an inning and allowing one run on a Marwin González RBI double. He was optioned to the Triple-A Norfolk Tides the next day before being recalled on June 30. He recorded his first career strikeout on July 3, fanning Los Angeles Angels infielder David Fletcher. In four appearances for the Orioles in 2021, he posted a 6.23 ERA with three strikeouts. He was outrighted to Triple-A Norfolk in April 2022 and released by the organization on July 18, 2022.
Independent League Stint (2022–2023)
On August 6, 2022, Mattson signed with the Washington Wild Things of the Frontier League. In 12 appearances for Washington, he recorded a 2.40 ERA with 23 strikeouts across 15 innings pitched. After the season, he was released when the team declined his contract option. He then signed with the Southern Maryland Blue Crabs of the Atlantic League of Professional Baseball on March 31, 2023.
With the Blue Crabs, Mattson made 18 appearances and logged a 3.32 ERA with 24 strikeouts and three saves in 19 innings pitched. His strong independent league performances helped him earn a return to affiliated baseball later that year.
Minnesota Twins Era (2023)
On June 22, 2023, Mattson signed a minor league contract with the Minnesota Twins organization. He spent the bulk of his time with the Double-A Wichita Wind Surge, appearing in 21 games and posting a 3.62 ERA with 42 strikeouts across 32 and a third innings. Following the season, Mattson elected free agency on November 6, 2023.
Pittsburgh Pirates Era (2023–Present)
On December 11, 2023, Mattson signed a minor league contract with the Pittsburgh Pirates. He began 2024 with the Double-A Altoona Curve before being promoted to the Triple-A Indianapolis Indians, compiling a 7–2 record with a 3.17 ERA and 89 strikeouts over 37 total games. On September 19, 2024, the Pirates selected his contract and added him to the active roster. He appeared in three games for Pittsburgh, posting a 5.06 ERA with six strikeouts over 5 and a third innings before being removed from the 40-man roster on November 4.
Mattson re-signed with the Pirates on a minor league contract on November 18, 2024. He opened 2025 with Indianapolis, posting a 2.50 ERA with 22 strikeouts and four saves across his first 16 outings. On May 20, 2025, the Pirates selected his contract again, bringing him back to the majors. On June 7, 2025, Mattson earned his first career win after tossing a scoreless seventh inning against the Philadelphia Phillies.
Notable Events and Milestones
One of the most meaningful moments of Mattson’s career came on June 7, 2025, when he earned his first major league win with a scoreless inning against the Philadelphia Phillies. His major league debut on May 7, 2021, with the Baltimore Orioles marked the realization of a journey that began in the lower levels of the Angels’ system. His selection to the Arizona Fall League in 2019 also stands as an early career milestone that showcased his prospect status.
Isaac Mattson Family
Family Background and Personal Life
Isaac Mattson is the son of Edward and Debra Mattson and was raised in Harborcreek, Pennsylvania, with seven siblings. His mother, Debra, passed away in July 2021. Family has remained an important part of his life throughout his baseball career, providing a steady foundation as he moved through the minor leagues and independent ball before reaching the majors.
Personal Life
Mattson married his wife, Devin, in November 2022. The couple welcomed their first child, a son, in February 2025. His family life has remained largely private, though his social media reflects his connection to both family and the baseball community.
2025 Season Performance
Isaac Mattson entered the 2025 season with the Pittsburgh Pirates organization after re-signing on a minor league deal in November 2024. He opened the year with the Triple-A Indianapolis Indians, where he was dominant in his first 16 outings, posting a 2.50 ERA with 22 strikeouts and four saves. His early consistency in Indianapolis earned him a quick return to the majors.
On May 20, 2025, the Pirates selected his contract and added him to the active roster. Mattson made an immediate impact, earning his first career win on June 7 against the Philadelphia Phillies with a scoreless seventh inning. His role in the Pittsburgh bullpen has continued to grow as he builds on the momentum of his breakthrough moment. With a strong minor league resume and a freshly secured first MLB win, Mattson has positioned himself as a reliable late-inning option for the Pirates heading into the second half of the 2025 season.