The NHL's coach of the year will come from the Eastern Conference.
Buffalo's Lindy Ruff, Tampa Bay's Jon Cooper and Pittsburgh's Dan Muse were announced on Friday as the three finalists for the Jack Adams Award.
The award is voted on by the NHL Broadcasters' Association and presented to the head coach "adjudged to have contributed most to his team's success" in the regular season.
Ruff, in his second season back with the Sabres, guided the team to its first playoff berth since 2010-11 and its first division title since 2009-10.
It's the fifth time Ruff has been nominated for the award, which is tied for the most in NHL history with Scotty Bowman, John Tortorella and Alain Vigneault. The 66-year-old Ruff won the award in 2005-06 in his previous tenure with the Sabres.
Cooper, the longest-tenured active coach in the NHL, led the Lightning to their ninth consecutive playoff berth this season.
He also became the second-fastest coach to reach 600 career wins this season, trailing only Bowman.
Cooper is seeking to win the award for the first time in his career after being named a finalist in two previous seasons with the Lightning.
Meanwhile, Muse led the Penguins to a surprising playoff berth in his first season as an NHL head coach.
The 43-year-old Muse will look to become the first rookie head coach to win the Jack Adams since Patrick Roy won it with the Colorado Avalanche in 2013-14.
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