Christoph Schubert had a goal and an assist, Daniel Alfredsson also scored once, and goalie Ray Emery stopped 31-of-32 Florida shots for the Senators, who have won eight of their first nine games under new head coach John Paddock.
Florida's lone goal was scored by Richard Zednik at the 5:29 mark of the second period.
Goaltender Tomas Vokoun made 43 saves on 47 shots despite being day-to-day with a sprained ankle for the Panthers, who have lost two in a row following a three-game winning streak.
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