Miller had to make only 13 saves and Raffi Torres registered three assists as the Sabres moved closer to clinching their first Northeast Division championship in three years.
Tim Kennedy got one past Panthers goalie Tomas Vokoun for a 2-1 Buffalo lead with 1:51 to play in the first period, and the Sabres made it 3-1 at 9:31 of the second period when Nathan Gerbe pounced on a loose puck in the high slot and netted a goal.
Florida's came from Jeff Taffe and Michael Frolik.
The Panthers have dropped four straight and sank further in the Eastern Conference standings, all but assuring they will miss the playoffs for the ninth straight season.
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