Cory Conacher and Vincent Lecavalier also scored for the Lightning, who are coming off a successful 2011-12 season in which they reached the second round of the Eastern Conference playoffs before falling to Boston.
Anders Lindback turned aside 27 shots for the Lightning.
The Capitals, meanwhile, couldn't secure a victory for Hall of Famer Adam Oates in his debut as Washington's head coach.
Braden Holtby made 28 saves for the Capitals.
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