Financial terms of the deal, announced Tuesday, weren't revealed.
The 23-year-old Galiardi played only 35 games last season because of wrist and forearm injuries. He finished with seven goals and eight assists. The Avalanche selected Galiardi in the second round of the 2007 draft.
Rissmiller, 32, played for five teams last season, including the Lake Erie of the American Hockey League. He was originally signed by the San Jose Sharks in June 2003 and has played in 192 NHL games.
Life's about opportunity and how you respond to that opportunity, and obviously he must have some swagger about him, some confidence about him, because he was solid. He made some good saves. He was 6-foot-3 on every shot, which is a good thing for a goalie. He played well. We got a win.
— Maple Leafs coach Mike Babcock on rookie goaltender Garret Sparks, who made 24 saves in his first NHL start, a 3-0 win vs. Oilers
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