On June 10, 2008, Sertich was traded from the Dallas Stars to the Colorado Avalanche in exchange for a conditional draft pick in 2009 NHL Entry Draft. Sertich was later signed to a multi-year contract with the Avalanche on June 24, 2008. Marty was assigned to AHL affiliate, the Lake Erie Monsters, for the 2008–09 season but had his season limited to only 24 games as he suffered two separate concussions.