Major junior Gleason was drafted in the second round, 36th overall, by the
London Knights in the 2014
Ontario Hockey League (OHL) draft. In August 2015, Gleason was one of 11 OHL players selected for the USA Hockey All-American Prospects Game, a game compiled of the top U.S. NHL draft eligible players. However, on October 7, 2015, Gleason was traded to the
Hamilton Bulldogs in exchange for a second round pick in the 2017 OHL Selection and a conditional 15th round pick in 2019. Despite his successful season, with 33 points in 66 games, Gleason was passed over in the
2016 NHL entry draft. As an overage player during the
2017–18 season, Gleason helped lead the Bulldogs to their first
Leyden Trophy as the regular season champion of the East division in the OHL. battling for position against
Kailer Yamamoto of the
Seattle Kraken in 2023.
Professional Undrafted in the NHL entry draft, Gleason signed a three-year entry-level contract with the
Dallas Stars on September 13, 2018. After attending the Stars' training camp, he was assigned to the
Texas Stars of the
American Hockey League (AHL). Gleason was recalled to the NHL on November 10, where he recorded his first NHL point on an assist of
Denis Gurianov's first NHL goal that night as the Stars lost the game in overtime to the
Nashville Predators. On November 22, he was reassigned to the Texas Stars. As a free agent from the Stars after five seasons within the organization, Gleason was signed to a two-year, $1.55 million contract with the Edmonton Oilers on July 2, 2023. Gleason impressed Oilers staff during the
2023–24 preseason and was considered a
dark horse to make the final roster. In spite of this, Gleason was a late cut from their roster and was re-assigned to their AHL affiliate, the
Bakersfield Condors, prior to the start of the season. He tallied two goals and seven assists for nine points through 14 games before being recalled to the NHL on December 7. During the
2024–25 season, on November 4, 2024, Gleason was traded by the Oilers to the
Philadelphia Flyers in exchange for
Ronnie Attard. He signed a one-year, two-way contract with the
Minnesota Wild for the season on July 2, 2025. ==Personal life==