Although Gauthier played less games in his final junior season, he was the recipient of the Guy Carbonneau Trophy at the conclusion of the 2014–15 season.[20] He also led the team to the President's Cup Trophy by scoring the game winning goal in double overtime of Game 7 against the Quebec Remparts.[21] On April 21, 2014, he signed an amateur tryout contract with the Toronto Marlies of the American Hockey League (AHL).[22]