Thomas Cosgrove (born June 14, 1996) is an American professional baseball pitcher in the Houston Astros organization. He has previously played in Major League Baseball (MLB) for the San Diego Padres and Chicago Cubs. He made his MLB debut in 2023.
Cosgrove attended Monsignor Farrell High School in Staten Island, New York. He attended Manhattan College and played college baseball for the Manhattan Jaspers. In 2016, he played collegiate summer baseball with the Wareham Gatemen and Chatham Anglers of the Cape Cod Baseball League.
The San Diego Padres selected Cosgrove in the 12th round, with the 348th overall selection, of the 2017 Major League Baseball draft.
Cosgrove spent his first professional season with the rookieâÂÂlevel Arizona League Padres and the LowâÂÂA Tri-City Dust Devils. In 13 games (6 starts), he logged a 1âÂÂ4 record and 3.22 ERA with 41 strikeouts in innings pitched. He spent 2018 with the SingleâÂÂA Fort Wayne TinCaps, appearing in 24 contests (21 starts) and going 3âÂÂ6 with a 3.71 ERA and 122 strikeouts in innings of work. In 2019, Cosgrove made only 9 appearances (all starts), splitting his time between the AZL Padres and the HighâÂÂA Lake Elsinore Storm. Cosgrove did not play in a game in 2020 due to the cancellation of the minor league season because of the COVID-19 pandemic.
Cosgrove returned to action in 2021, and made 22 appearances for the DoubleâÂÂA San Antonio Missions, posting a 2.36 ERA with 32 strikeouts in innings pitched. Cosgrove split the 2022 season between San Antonio and the TripleâÂÂA El Paso Chihuahuas. In a careerâÂÂhigh 48 appearances, he registered an 8âÂÂ2 record and 3.72 ERA with 82 strikeouts in innings of work. On November 15, 2022, the Padres added Cosgrove to their 40-man roster to protect him from the Rule 5 draft.
Cosgrove was optioned to Triple-A El Paso to begin the 2023 season. On April 26, 2023, Cosgrove was promoted to the major leagues for the first time. He made 54 appearances for San Diego during his rookie campaign, compiling a 1-2 record and 1.75 ERA with 44 strikeouts and one save across innings pitched.
Cosgrove made 18 appearances for the Padres in 2024, but struggled to an 0-1 record and 11.66 ERA with 15 strikeouts over innings of work. He was optioned to Triple-A El Paso to begin the 2025 season. In 4 appearances for the Chihuahuas, Cosgrove posted a 1âÂÂ0 record and 7.36 ERA with 2 strikeouts across innings pitched. Cosgrove was designated for assignment by the Padres on April 6, 2025.
On April 10, 2025, Cosgrove was traded to the Chicago Cubs in exchange for cash considerations; he was subsequently optioned to the Triple-A Iowa Cubs. In two appearances for Chicago, he recorded a 2.25 ERA with three strikeouts over four innings of work. Cosgrove was designated for assignment by the Cubs on August 31. He cleared waivers and was sent outright to Triple-A Iowa on September 3. Cosgrove elected free agency following the season on November 6.
On January 29, 2026, Cosgrove signed a minor league contract with the Houston Astros.