The win was the ninth in 10 games for the defending Stanley Cup champions, who have outscored the opposition 49-13 during that span, with Rask and Tim Thomas combining for four shutouts.
Rask, who stopped 25 shots for the 11th shutout of his career, has allowed one goal in his past four starts.
In Toronto, Jonas Gustavsson stopped all 24 shots he faced for his second career shutout, leading the Maple Leafs.
Phil Kessel, Tim Connolly, Mikhail Grabovski and Clarke MacArthur scored for Toronto.
In New York, Marian Gaborik scored 3:29 into overtime for the Rangers, who outlasted Florida and moved to the top of the NHL standings with their eighth win in nine games.
Gaborik took a drop pass from Derek Stepan in the high slot and slapped in a drive for his 23rd goal of the season.
New York (25-9-4) stayed one point ahead of Boston in the Eastern Conference, but jumped one point in front of West-leading Vancouver, which was idle.
Defenseman Anton Stralman and captain Ryan Callahan also scored for the Rangers.
In Philadelphia, James van Riemsdyk’s second goal on the power play with 32.8 seconds remaining lifted the Flyers.
Brent Seabrook and Patrick Kane scored 25 seconds apart late in the third period to tie it, but van Riemsdyk made sure the Flyers shook off the disappointment from their Winter Classic loss.
Scott Hartnell, Harry Zolnierczyk and van Riemsdyk scored goals in a span of 4:20 in the second period, and Jakub Voracek also scored for the Flyers.
SENATORS 4, LIGHTNING 1
In Ottawa, Daniel Alfredsson had a goal and two assists, Craig Anderson made 35 saves and the Senators extended their winning streak to four games.
Alfredsson got his second assist on Zack Smith’s goal at 16:34 that made it 3-1. Alfredsson scored into an empty net at 19:07.
STARS 4, PREDATORS 1
In Nashville, Tenn., Mike Ribeiro scored two goals in the first period and Dallas beat Nashville, ruining the return of Predators captain Shea Weber from a concussion.
Weber had missed four games since being hurt Dec. 23 in a loss at Dallas in a collision with Stars defenseman Mark Fistric. The Predators announced Thursday at the morning skate that the defenseman had been cleared to play.
and Nashville had a franchise-record seventh straight sellout for Weber’s return.
Edmonton at St. Louis, 8 p.m.