TORONTO - Derek Stepan scored the go-ahead goal with 1:31 remaining in regulation as the New York Rangers downed the league-worst Toronto Maple Leafs 4-2 on Thursday.

Stepan's one-time goal, which came as the result of defensive-zone giveaway by Morgan Rielly, came 59 seconds after Colin Greening tied the score at two with his first goal as a member of the Leafs.

Derick Brassard, with two, and Mats Zuccarello also scored for the Rangers (33-19-6). Antti Raanta made 35 saves for the win.

P.A. Parenteau also scored for the Leafs (20-27-9) as Jonathan Bernier stopped 16 shots in defeat.

Toronto, which has dropped 14 of its last 18 games, remains last in the league with 49 points and may be forced to play without leading scorer Leo Komarov in the days ahead.

Komarov was ejected from Thursday's action following a nasty elbow to the head of Rangers captain Ryan McDonagh late in the first period. The 29-year-old was dealt a match penalty for an illegal check to the head and could face supplemental discipline from the league.

McDonagh, who returned from a concussion only one night earlier after missing four games, was held out the final two periods for "precautionary reasons".

The Leafs controlled play against the Rangers, outshooting them 11-3 at one point in the first period and 37-20 overall while landing the game's first goal from Parenteau. Parenteau inadvertently redirected a Viktor Loov point shot with his left skate, his 15th goal this season standing on video review.

A likely trade chip for the Leafs ahead of the Feb. 29 trade deadline, Parenteau has seven points in seven games this month.

Bernier was given an opportunity to start and reclaim Toronto's crease with apparent no. 1 James Reimer struggling. The 27-year-old was sharp with limited action, but still dropped his sixth straight start.

He gave up three goals on 19 shots. His last victory came on Jan. 6 when he pitched a 39-save shutout in Anaheim.

The 27-year-old entered the night with the second-worst save percentage in the league this season (.899) and the worst mark at even-strength among goaltenders with at least 20 starts (.905).

New York has been amongst the hottest teams in the league of late. The club, which trails only Washington in the Metropolitan Division, had a six-game point streak (5-0-1) snapped at home against Chicago on Wednesday night.

The Rangers lead the Eastern Conference with 21 points since Jan. 16.

Komarov, who leads the Leafs with 18 goals and 35 points this season, could be facing his first NHL suspension for the hit on McDonagh. His absence would further dampen a Toronto team that's playing without injured forwards James van Riemsdyk, Tyler Bozak, Joffrey Lupul, Shawn Matthias, and Josh Leivo, as well as defencemen Jared Cowen and Matt Hunwick.

Hunwick, a former Ranger, was the latest to join the injured crew, forced to miss a rematch with his old team because of an undisclosed ailment. He was replaced by the 23-year-old Loov, who was making his NHL debut.

Thursday marked the first game back in Toronto for the Leafs following a five-game road trip. The club, which has played the fewest home games in the league this season, plays eight of their next 10 games at the Air Canada Centre.