MONTREAL -- Defenceman Medric Mercier scored the game-winner on a power-play at 16:47 of the final period to cap a late two-goal rally as fourth-seeded Ottawa surprised top-seeded McGill 3-2 in their OUA East men's hockey semifinal opener at McConnell Arena, Wednesday.

The upstart Gee-Gees, who have now won three of four meetings with McGill this season, are in position to deliver a knockout punch should they defeat the Redmen in Game 2 on Friday at 7:30 p.m. in the uOttawa Minto Sports Complex. A McGill victory would force a deciding game back in Montreal on Sunday at 7 p.m.

McGill, which is ranked No. 4 in the national Top 10 and had the nation's third-best penalty-killing success rate at 88.4 per cent during the regular season, were handcuffed when centre Samuel Tremblay, their top penalty-killing forward, was penalized three times, with two of them leading to goals. The Gee-Gees went 2-for-4 on the power-play, while McGill was 1-for-3.

Ottawa took advantage of a sluggish McGill start by scoring before the game was three minutes old when centre Jacob Hanlon deflected a cross-ice feed past McGill netminder Louis-Philip Guindon at 2:55.

The Redmen awoke in the second period with goals from Jerome Verrier at 4:00 and Guillaume Gauthier, on the power-play, with his fifth of the post-season at 14:22.

But McGill, took three of their four penalties in the final stanza and the Gee-Gees capitalized twice with power-play goals from Marco Azzano at 8:26 to tie the score at 2-2 and the aforementioned Mercier marker with just over three minutes remaining.

"We had one good period out of three and needed to show the type of urgency that we had in the second period," said McGill bench boss Kelly Nobes, who was at a loss for words. "A full 60 minutes, that's what playoff hockey is all about. And clearly our penalty-kill has to be better."

Graham Hunt, a sophomore netminder from Concord, N.H., who was starting in place of the injured Anthony Brodeur, turned aside 28 of 30 shots for the win in his first start of the 2018 post-season.

Guindon saved 26 of 29 in a losing cause for the Redmen.

The game was the 194th lifetime meeting between McGill and Ottawa and the Redmen record fell to 102-82-10, including a slight 15-14 edge in post-season play.

FACES IN THE CROWD: Among the McGill hockey alumni spotted in the crowd were former Redmen Brent Bannerman (1986-1990), Ron Wawaruk (1991-92), Dr. Jay McMullan (1981-1984), Danny Gubiani (1981-1984), Ken Covo (1976-1981) and Mike Nelson (1978-1984). Also on hand was former Martlets captain Shauna Denis (2003-2008), who led McGill to their first national women's crown in 2008 and now works for the NHL's Montreal Canadiens.

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