Gravel, a defenseman, was a fifth-round pick (No. 148) of the Los Angeles Kings in the 2010 NHL Draft. He played four seasons for St. Cloud State University before signing an amateur tryout contract with Manchester of the American Hockey League in 2014.
Gravel agreed to a one-year contract to continue playing for Manchester on Aug. 4, 2014. He established himself with 15 points (six goals, nine assists) in 58 regular-season games and helped the Monarchs win the Calder Cup with five assists in 19 playoff games.