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.
Yeah, it was a pretty special moment for me. Today was my Dad's [55th] birthday. I have a lot of family in town, so it was a special moment for me to score my first one today. A win definitely would have capped it off, but you can't have everything.
— Sabres rookie Jack Eichel after scoring a goal in his National Hockey League debut
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