He was then drafted in the 15th round of the 2014 Major League Baseball draft by the Toronto Blue Jays, and was assigned to the Vancouver Canadians of the Northwest League. In 70 games, McBroom batted .297 with 11 home runs and 59 RBI. His 11 home runs tied for the league lead. McBroom began the 2015 season with the Lansing Lugnuts. On June 5, he was named a Midwest League midseason All-Star. At that time, McBroom was batting .307 with 16 doubles. On August 24, McBroom was named the 2015 Midwest League MVP, becoming the third Blue Jays prospect to win the award after Kevin Pillar and Brian Dopirak. McBroom played in 127 games in 2015 for Lansing, and batted .315 with 12 home runs and 90 RBIs. He was assigned to the Advanced-A Dunedin Blue Jays to open the 2016 minor league season. McBroom played in 119 games for Dunedin in 2016, as well as nine games with the Double-A New Hampshire Fisher Cats. He would bat a combined .266 with 22 home runs and 85 RBIs. After the 2016 season, the Blue Jays assigned McBroom to the Mesa Solar Sox of the Arizona Fall League. He appeared in seven games for the Sox before being removed from the roster due to injury. He began 2017 with New Hampshire Fisher Cats.