Miles James Mastrobuoni Bio
Miles James Mastrobuoni is an American professional baseball utility player currently playing for the Seattle Mariners of Major League Baseball. Born on October 31, 1995, in Livermore, California, Mastrobuoni has built a reputation as a versatile defender capable of playing multiple positions across the diamond. He made his Major League Baseball debut with the Tampa Bay Rays in September 2022 after being selected in the 14th round of the 2016 MLB Draft. Throughout his career, Mastrobuoni has showcased his adaptability, playing for the Tampa Bay Rays, Chicago Cubs, and Seattle Mariners while representing Italy in the 2023 World Baseball Classic.
Early Life and Background
Mastrobuoni grew up in Livermore, California, where he attended Granada High School. His passion for baseball developed during his high school years, where he demonstrated the skills that would eventually carry him to the professional ranks. After graduating from Granada High School, Mastrobuoni began his collegiate baseball career at the College of San Mateo, playing for the Bulldogs for two seasons. His performance at the junior college level attracted attention from four-year programs seeking talented players to strengthen their rosters.
Seeking to continue his development at a higher level of collegiate competition, Mastrobuoni transferred to the University of Nevada, Reno, where he played for the Nevada Wolf Pack. The transition to the Mountain West Conference presented new challenges and opportunities for growth. During the summer of 2015, Mastrobuoni further honed his skills by playing summer league baseball for the Rochester Honkers of the Northwoods League, a prestigious collegiate summer baseball circuit known for developing professional prospects.
Path to Professional Baseball
After completing his collegiate career with the Nevada Wolf Pack, Mastrobuoni entered the 2016 Major League Baseball Draft. The Tampa Bay Rays selected him in the 14th round with the 420th overall selection. Being drafted in the 14th round required Mastrobuoni to prove himself through the minor leagues, as later-round picks typically face longer odds of reaching the majors. He began his professional career with the Low-A Hudson Valley Renegades, where he appeared in 61 games and hit .267, demonstrating immediate readiness for professional competition.
Miles James Mastrobuoni Career
Minor League Development (2016–2021)
Mastrobuoni steadily climbed through the Tampa Bay Rays farm system over several seasons. In 2017 with the Single-A Bowling Green Hot Rods, he played 104 games and batted .264 with three home runs, 39 RBI, and 18 stolen bases, showing the combination of contact hitting and basestealing ability that would define his game. The following season in 2018, he split time between the High-A Charlotte Stone Crabs and Double-A Montgomery Biscuits, combining to hit .285 in 330 at-bats with one home run and 39 RBI.
The 2019 season saw Mastrobuoni spend the majority of his time with Montgomery, also appearing in four games for the Triple-A Durham Bulls. He played 107 games for the Biscuits, hitting .299 with four home runs, 34 RBI, and 15 stolen bases. The 2020 season was lost due to the COVID-19 pandemic canceling all minor league games, forcing Mastrobuoni to wait another year before continuing his progression. He returned in 2021, playing for both Montgomery and Durham, and in 106 total games, he batted .296 with five home runs and 45 RBI, continuing his consistent offensive production.
Tampa Bay Rays Breakthrough (2022)
Mastrobuoni began the 2022 season with Triple-A Durham, where he posted the best offensive numbers of his minor league career. In 129 games with the Bulls, he hit .300 with career highs in home runs with 16, RBI with 64, and stolen bases with 23. His performance earned him a spot on the 40-man roster, and on September 22, 2022, the Rays promoted him to the majors for the first time. The following day, Mastrobuoni collected his first MLB hit, a single off Anthony Bass of the Toronto Blue Jays. He appeared in eight games for the Rays that season, going 3-for-16 at the plate with a walk and a stolen base.
Chicago Cubs (2023–2024)
On November 15, 2022, the Tampa Bay Rays traded Mastrobuoni to the Chicago Cubs in exchange for pitcher Alfredo Zárraga. He made Chicago’s Opening Day roster in 2023, starting at right field and batting ninth against the Milwaukee Brewers in the season opener. On July 21, 2023, Mastrobuoni hit his first career home run, a significant milestone in his development as a major league player, off Jack Flaherty of the St. Louis Cardinals. In 60 games for the Cubs during his rookie season, he slashed .241/.308/.301 with one home run, five RBI, and 13 stolen bases.
The 2024 season proved more challenging for Mastrobuoni. He made 50 appearances for Chicago, batting only .194 with no home runs, four RBI, and two stolen bases. On January 9, 2025, the Cubs designated Mastrobuoni for assignment following the acquisition of Matt Festa, bringing his tenure with the organization to an end after two seasons.
Seattle Mariners Era (2025–Present)
On January 14, 2025, the Seattle Mariners acquired Mastrobuoni from the Cubs in exchange for cash. He began the season as a utility player for the Mariners before being sent to Triple-A Tacoma following the acquisition of Josh Naylor. Mastrobuoni returned to the majors within a week when Ben Williamson was demoted but was sent back to Tacoma after the Little League Classic in August. He played in the final game of the regular season, hitting a double that became the final extra base hit allowed by Clayton Kershaw of the Los Angeles Dodgers in his career. The Mariners added Mastrobuoni to their roster for the American League Championship Series, replacing Luke Raley. He finished the 2025 regular season batting .250/.324/.296 with one home run, 12 RBI, and six stolen bases in 76 games.
In 2026, Mastrobuoni’s season was interrupted by injury. On April 20, 2026, he was placed on the 60-day injured list due to a calf injury. He was activated by Seattle on June 10 and subsequently cleared waivers, being sent outright to Triple-A Tacoma on June 25.
Playing Style and Strengths
Mastrobuoni has established himself as a true utility player, capable of playing multiple positions across the field. His speed stands as one of his primary assets, consistently ranking among league leaders in stolen bases throughout his minor league career. He displays a patient approach at the plate, drawing walks and working counts to get on base. His defensive versatility allows managers flexibility in constructing lineups, as he can fill various roles depending on matchups and game situations.
Notable Events and Milestones
Several significant moments define Mastrobuoni’s career thus far. His first MLB hit on September 23, 2022, against the Toronto Blue Jays marked his arrival at the sport’s highest level. His first career home run on July 21, 2023, against Jack Flaherty represented another milestone as a major league hitter. The 2025 season brought additional memorable experiences, including his inclusion on the Mariners’ postseason roster and his final regular-season double off Clayton Kershaw, a moment that added him to baseball history.
Miles James Mastrobuoni Career Wins
Throughout his professional career spanning from 2016 to 2026, Mastrobuoni has accumulated victories across multiple minor league levels and parts of three Major League Baseball seasons. His most productive stretch came during his time with the Triple-A Durham Bulls from 2021 to 2022, where he posted career-high numbers in several categories. At the major league level, he has contributed across three organizations while maintaining his role as a versatile bench player capable of filling multiple positions.
Major League Baseball Highlights
Through June 10, 2026, Mastrobuoni has played in 134 Major League Baseball games across three seasons with Tampa Bay, Chicago, and Seattle. He has compiled a career batting average of .231 with two home runs and 21 RBI. His most significant contributions came during his time with the Chicago Cubs in 2023, where he appeared in 60 games and stole 13 bases while learning the nuances of major league pitching.
Minor League Achievements
Before reaching the majors, Mastrobuoni enjoyed considerable success in the minor leagues. His 2022 season with Triple-A Durham proved to be his best, as he hit .300 with 16 home runs, 64 RBI, and 23 stolen bases in 129 games. He also had strong campaigns with Double-A Montgomery, including a 2019 season where he hit .299 in 107 games. His consistent performance across multiple levels of the minor leagues demonstrated his readiness for major league competition.
International Career
Mastrobuoni represented Italy in the 2023 World Baseball Classic, showcasing his heritage and contributing to international baseball. Over five games in the tournament, he batted 5-for-18 with two doubles, two RBI, three strikeouts, and a stolen base. His participation in the WBC provided valuable international experience and the opportunity to compete against players from around the world while representing his family’s country of origin.
2025 Season Performance
The 2025 season marked a transitional year for Mastrobuoni as he joined the Seattle Mariners organization following two seasons with the Chicago Cubs. He split time between Triple-A Tacoma and the major league roster, appearing in 76 games for the Mariners. His offensive production included a .250 batting average with a .324 on-base percentage, one home run, 12 RBI, and six stolen bases. The highlight of his season came when the Mariners added him to their roster for the American League Championship Series, giving him postseason experience with a division-winning team.
Personal Life
Mastrobuoni’s educational background includes Granada High School in his hometown of Livermore, California, followed by two seasons at the College of San Mateo and a transfer to Nevada Wolf Pack, where he completed his collegiate baseball career. He remains active on social media, connecting with fans through his Instagram account. His career has been characterized by perseverance, having worked his way from a 14th-round draft pick to becoming a Major League Baseball player capable of contributing at the sport’s highest level.