Joshua-Douglas James Naylor Bio
Joshua-Douglas James Naylor is a Canadian professional baseball player and first baseman for the Seattle Mariners of Major League Baseball. Naylor has played in MLB for the San Diego Padres, Cleveland Indians / Guardians, and Arizona Diamondbacks after being selected 12th overall in the 2015 MLB draft by the Miami Marlins.
Early Life and Background
Joshua-Douglas James Naylor was born on June 22, 1997, in Mississauga, Ontario, and grew up in the Toronto area. He attended St. Joan of Arc Catholic Secondary School and played for the Ontario Blue Jays travel program as a youth, gaining attention as one of Canada’s top high school prospects.
Naylor represented Canada in junior international tournaments beginning at age 15 and became the first Canadian to play in three editions of the U-18 Baseball World Cup. His early exposure to national competition and U.S. showcase events established him as a high draft prospect prior to the 2015 MLB draft.
Path to Baseball
Naylor developed through elite junior programs in Ontario and earned invitations to premier U.S. showcase events, including the MLB Junior Select Home Run Derby and the Perfect Game All-American Classic during his high school years. He was ranked among the top high school prospects nationwide and committed to Texas Tech before signing professionally.
Selected by the Miami Marlins with the 12th overall pick in 2015, Naylor began his professional career in the Marlins’ rookie and Single-A system before being traded to the San Diego Padres in 2016. He rose through Single-A, Double-A and Triple-A, appearing in the All-Star Futures Game as a top prospect prior to his major league debut.
Joshua-Douglas James Naylor Career
Early Career (2015–2019)
Naylor signed with the Miami Marlins after the 2015 draft and debuted professionally with the rookie-level GCL Marlins, posting strong contact numbers in limited action. In 2016 he opened in Single-A and was part of a multi-player trade that sent him to the San Diego Padres, where he continued to advance through the minor leagues.
Across 2016–2018, Naylor progressed from Advanced-A to Double-A and Triple-A, showing developing power and run production. He made his major league debut with the San Diego Padres on May 24, 2019, at Rogers Centre against the Toronto Blue Jays and recorded his first MLB hit the following day.
San Diego Padres Breakthrough (2019–2020)
Naylor reached the major leagues with the Padres in 2019 and finished that season as a regular contributor, recording eight home runs and 32 RBIs in 94 games. He split time among outfield and infield positions as the Padres evaluated his defensive fit while he adjusted to big-league pitching.
During a shortened 2020 season, Naylor appeared in 18 games for the Padres before being included in a trade to the Cleveland Indians at the August trade deadline. His early MLB seasons featured flashes of power and times of defensive adjustment as he transitioned toward a primary infield role.
Cleveland Indians / Guardians Breakthrough (2020–2024)
The San Diego Padres traded Naylor to the Cleveland organization in August 2020. He made his first postseason appearances with Cleveland in 2020 and set a franchise and modern playoff mark by recording hits in his first five career postseason plate appearances.
Naylor’s tenure in Cleveland included both setbacks and breakthroughs. He suffered a season-ending ankle injury in 2021 but returned to become a full-time first baseman by 2022, lowering his strikeout rate and increasing power. In 2023 Naylor posted a strong regular season and received the Tip O’Neill Award as Canada’s top professional baseball player. He was named an MLB All-Star in 2024 and finished that season with 31 home runs and 108 RBIs.
Arizona Diamondbacks (2025)
After the 2024 season, Cleveland traded Naylor to the Arizona Diamondbacks. He began the 2025 season with Arizona and produced a productive first half, including a notable walk-off grand slam for the Diamondbacks in June of 2025. By the time of his midseason move, he had compiled power and on-base numbers that made him a trade target at the July deadline.
Seattle Mariners Era (2025–Present)
The Diamondbacks traded Naylor to the Seattle Mariners on July 24, 2025. He made an immediate impact in Seattle down the stretch; in late September he hit a bases-clearing double that helped the Mariners clinch a postseason berth and later stole his 30th base, becoming one of the few first basemen in MLB history to reach at least 20 home runs and 30 stolen bases in a single season.
Naylor finished the 2025 regular season combining his Diamondbacks and Mariners numbers with strong offensive production, then produced a standout postseason for Seattle. He batted .340 with three home runs and five RBIs through the Mariners’ postseason run, helping the team reach the AL Championship Series. Following the season, Naylor re-signed with the Mariners on a multiyear contract that runs through 2030.
Playing Style and Strengths
Naylor profiles as a power-oriented left-handed hitter who developed improved contact skills and plate discipline after settling in at first base. He is noted for his run production in late innings and for adding baserunning aggressiveness that produced an uncommon combination of home run power and stolen-base ability for a first baseman.
Notable Events and Milestones
Key milestones include his first MLB hit during his 2019 debut week, a dramatic multi-homer performance in 2022 that included a go-ahead extra-inning blast, an MLB All-Star selection in 2024, two Tip O’Neill Awards, and becoming one of the rare first basemen to combine 20-plus home runs with 30-plus stolen bases in a season.
Joshua-Douglas James Naylor Career Wins
Naylor’s career achievements are measured primarily by offensive production rather than wins. Through June 28, 2026, his major league totals include 112 home runs, 469 runs batted in, and a career batting average of .268. Those totals reflect steady power and run creation across stints with multiple teams.
MLB Highlights
Naylor’s most prominent MLB highlights include his 2024 All-Star selection, the Tip O’Neill Awards in 2023 and 2025 recognizing him as Canada’s top player, and postseason contributions in several playoff appearances. His 2025 late-season and postseason play with the Seattle Mariners represent a career-defining stretch.
Other Wins & Perfromances
At the junior international level, Naylor earned All-World Team honors at the 2015 U-18 Baseball World Cup, where he led or ranked among tournament leaders in several offensive categories. His junior national team success was a significant early credential that preceded his first-round draft selection.
Joshua-Douglas James Naylor Family
Family Background and Baseball Lineage
Naylor comes from a baseball family. His brother Bo Naylor is a catcher for the Cleveland Guardians organization, while younger brother Myles Naylor is in the Oakland Athletics farm system. The family includes other extended relations who have also played at high competitive levels.
Personal Life
Naylor married Chantel Collado on January 4, 2025. The couple resides in Mississauga, Ontario. Their first child, a daughter, was born in 2025. Naylor’s off-field profile includes community ties in Canada and a public presence as one of the country’s leading professional baseball players.
2025 Season Performance
The 2025 season was a pivotal year for Naylor. He began the year with the Arizona Diamondbacks, produced impactful offensive results including a walk-off grand slam, and was traded midseason to the Seattle Mariners, where he helped the club clinch a postseason berth and added notable postseason production.
Naylor’s combined 2025 performance showcased his blend of power and baserunning, and his postseason batting line underscored his capacity to contribute in high-leverage moments. The season culminated with a new multiyear contract with the Mariners and a second Tip O’Neill Award recognizing him as Canada’s top professional player for the year.