Leighton turned aside 17 shots to post his latest shutout after also blanking Montreal in Games 1 and 2. But he got plenty of help from the tough Flyers' defense -- the Habs managed only one shot on net in the second period as Philadelphia moved to within one win of the Stanley Cup finals.
Claude Giroux and Ville Leino got second-period goals past Canadiens netminder Jaroslav Halak. Giroux tallied 5:41 into the frame to break a scoreless tie and nine minutes later Leino tallied on a breakaway pass from Chris Pronger to make it 2-0.
Giroux added an empty-netter with 1:13 left in the game after Montreal pulled Halak for an extra attacker.
Halak turned aside 24 shots in Montreal's loss.
The Habs will face elimination when the series returns to Philadelphia for Game 5 Monday.