As a youth, Petan played in the 2007 and 2008 Quebec International Pee-Wee Hockey Tournaments with a minor ice hockey team from North Vancouver. Petan, who played in the Western Hockey League beginning in the 2010–11 season with the Portland Winterhawks, was rewarded for his outstanding performance in the 2012–13 season by being named to the 2013 WHL West First All-Star Team. Petan led the WHL with 74 assists, and shared the overall points title with Brendan Leipsic, finishing with 120 points in 68 games. Petan scored 9 goals with 19 assists in 21 playoff games and was +13 with 16 penalty minutes. The Winterhawks reached the 2013 Memorial Cupchampionship game, losing 6–4 to the Halifax Mooseheads. Petan scored one goal and nine assists and was +1 in five Memorial Cup games. In the 2013–14 season, Petan had 35 goals and led the WHL with 78 assists, finishing +47 with 69 penalty minutes. Portland finished first in the U.S. Division and reached the WHL Finals for the fourth straight year. The Winterhawks lost to the eventual Memorial Cup champions, the Edmonton Oil Kings. Petan scored 7 goals with 21 assists and was +7, with 38 penalty minutes in 21 playoff games. In December 2013, Petan signed a three-year, entry-level contact with the Winnipeg Jets. In 2014–15, Petan returned to the Winterhawks for his final year of junior eligibility and finished with 89 points in the regular season and another 28 points in the playoffs.
Professional
After finishing major junior hockey, Petan immediately jumped to the NHL, starting the 2015–16 season with the Winnipeg Jets. He scored a goal in his NHL debut for the Jets on October 8, 2015, against Tuukka Rask of the Boston Bruins. On November 19, 2015, he was reassigned to the Jets' American Hockey League affiliate, the Manitoba Moose. On March 17, 2016, the Jets recalled Petan. Petan made the Jets' opening night roster for the 2017–18 season, but was reassigned to the Moose after playing in six games. He scored at a point-per-game pace with Manitoba, registering 15 goals and 37 assists in 52 games. He was recalled to the Jets on two occasions finishing with 2 goals in 15 games. On August 1, 2018, following the completion of his entry-level contract earlier in the off-season, Petan was signed as a restricted free agent to a one-year, two-way extension with the Jets. Petan, now waiver eligible, began the 2018–19 season with the Jets. He played sparingly for the Central Division-contending Jets, appearing in just 13 games approaching the trade deadline before he was traded to the Toronto Maple Leafs in exchange for Pär Lindholm on February 25, 2019. On March 21, Petan signed a two year contract extension with the Leafs.
