Petrovic was selected by the Florida Panthers in the second round, 36th overall, of the 2010 NHL Entry Draft from the Red Deer Rebels in the Western Hockey League (WHL).

[5] He made his professional debut in the American Hockey League (AHL) playoffs with the San Antonio Rampage after the 2011–12 season.

Two weeks later on February 9 in a 7–4 Panthers win over the Buffalo Sabres at First Niagara Center, he picked up a goal and an assist but fought Evander Kane three times.

[9] During his seventh season with the Panthers in 2018–19, having slowed his production and effectiveness on the third-pairing with Florida producing just 1 assist in 26 games, Petrovic was traded to the Edmonton Oilers in exchange for Chris Wideman and a conditional third-round pick in 2019 on December 30, 2018.

[10] In the 2019 offseason, as an unrestricted free agent, Petrovic signed a professional tryout contract with the Boston Bruins.

[12] He began the pandemic delayed and shortened 2020–21 season, with the Flames AHL affiliate, the Stockton Heat, producing 12 points in just 17 games.