Career
Callahan was drafted 180th overall by the Detroit Red Wings in the 2009 National Hockey League Entry Draft. Junior
During the 2010-2011 season, Callahan helped Kelowna to a British Columbia Division title, by finishing second among team leaders with 23 goals, and third among team leaders with 31 assists. Callahan was named the WHL player of the week for the week ending November 6, 2010, after recording five goals and seven assists in four games.
During Callahan"s three seasons with the Kelowna Rockets, he registered 57 goals, 128 points, and 440 penalty minutes in 204 games played.
Professional
On May 4, 2010, the Detroit Red Wings signed Callahan to a three-year entry level contract. Callahan made his AHL debut with the Grand Rapids Griffins on October 8, 2011.
During his first professional season, which was limited to 48 games due to injuries, Callahan finished second among AHL rookies with 14 fighting majors. During the 2012-2013 season, Callahan skated in 71 of 76 games in his second season in the AHL. On January 19, 2013, Callahan recorded his first professional hat-trick in a game against the Rockford IceHogs.
On March 25, 2014, Callahan made his National Hockey League debut for the Detroit Red Wings in a game against the Columbus Blue Jackets.
During the 2013-2014 season, Callahan skated in 70 games in his third season in the AHL, and finished among the Griffins" leading scorers with 26 goals (2nd) and 44 points (4th). On July 17, 2014, the Detroit Red Wings signed Callahan to a one-year contract. During the 2014-2015 season, Callahan recorded 16 goals and 22 assists in 48 games during his fourth season in the AHL, before a knee injury sidelined him for the remainder of the season.
On July 13, 2015, the Detroit Red Wings signed Callahan to a one-year contract extension.
Callahan"s only goal in the tournament was a game-winning goal against Switzerland in the final preliminary-round game to give the team a bye into the medal round.