Despite making an impression with the Avalanche in the pre-season, Stoa was assigned to the Avalanche's AHL affiliate, the Lake Erie Monsters to begin the 2009–10 season. On October 13, 2009, he scored his first professional goal with Lake Erie against the San Antonio Rampage in a 4–1 defeat. Stoa made his NHL debut with the Avalanche against the Calgary Flames on December 13, 2009. In his fifth recall to the Avalanche, Stoa scored his first NHL goal in a 5–2 defeat to the Chicago Blackhawks on April 9, 2010. Stoa finished the season scoring 40 points with the Monsters, co-leading the AHL with 23 goals among rookies.
