Jean-Pierre Vigier and Ilya Kovalchuk also scored for Atlanta, which won its fourth straight game and fifth in a row against Florida. The Thrashers are 5-0-1 in their last six games.
Olli Jokinen scored for Florida and Ed Belfour stopped 23 shots. The Panthers have lost a season-high six straight games, their longest winless streak since going 0-6-1 from March 19-29, 2003.
The Thrashers took a 2-1 lead with a power-play goal at 4:01 of the second. Bobby Holik's shot from the right circle went behind the net and drifted back in front of the crease. Metropolit came from behind and slid the puck past Belfour.
Kovalchuk scored an empty-net goal at 19:25 of the third.
Florida tied it 1-1 on Jokinen's goal at 17:11 of the first. Ville Peltonen's shot from the left circle hit Jokinen in front, who was pushed into Lehtonen. The puck went off Jokinen and into the net. It was the first goal for Florida in 218 minutes, 42 seconds, a franchise record.
Atlanta took a 1-0 lead at 6:26. Vigier's shot from the right circle was blocked by Belfour. The puck came loose in front of the crease, and Vigier picked up the rebound and poked it across the goal line.
Florida's Gregory Campbell was awarded a penalty shot at 1:56 of the third period after being pulled down from behind by Steve McCarthy on a breakaway. His shot was blocked by Lehtonen.
Notes: Florida's Joe Nieuwendyk sat out with back spasms. ... Thrashers C Jim Slater missed the game with an apparent foot injury.