The team announced the hiring in a release issued on Tuesday afternoon.
Sacco spent four seasons as the Colorado Avalanche coach before being fired in April after the team missed the playoffs for a third straight year. He finished with a 130-134-40 record and was an NHL coach of the year finalist in 2010 after leading the Avalanche to the playoffs in his first season.
Rolston finished last season as the Sabres interim coach after Lindy Ruff was fired in February. Rolston was hired as the team's full-time coach in May, when he fired former assistants James Patrick and Kevyn Adams.