The 24-year-old Gagner, the No. 6 pick in the 2007 draft, had 10 goals and 27 assists in 67 games last season. He had 101 goals and 194 assists in 481 games in seven seasons with the Oilers.
The 28-year-old Purcell had 12 goals and 30 assists in 81 games last season. In 401 games in seven seasons with Los Angeles and Tampa Bay, he has 75 goals and 153 assists.