VANCOUVER - A disastrous third period cost the Ottawa Senators dearly in their push for a playoff spot.

Matt Bartkowski had two goals and an assist for the first three-point game of his career Thursday as the Vancouver Canucks stormed back from a 3-2 deficit after 40 minutes to beat the Senators 5-3 and snap Ottawa's four-game winning streak.

"We definitely didn't play our best game," said Senators goalie Craig Anderson, who finished 31 stops. "We had the lead going into the third and we just came out flat. They took momentum and that was the night."

Jake Virtanen, with a goal and an assist, scored the winner in the third as Vancouver (24-24-12) won back-to-back games at home for the first time since late December. Emerson Etem also scored twice for the Canucks, while Linden Vey chipped in with two assists. Ryan Miller made 27 saves.

Mike Hoffman, Mark Stone and Bobby Ryan replied for Ottawa (29-27-6), while Dion Phaneuf and Jean-Gabriel Pageau each added two assists as the Senators dropped to 18-2-1 when leading after two periods.

"It's a game of mistakes," said Anderson. "We made mistakes, they capitalized."

Ottawa is looking to make another late charge into the post-season after finishing 2014-15 on an improbable 23-4-4 run, but Thursday's loss kept the Senators four points back of Pittsburgh for the second wild-card berth in the Eastern Conference. The Penguins have three games in hand, and there are also three teams positioned between the clubs.

Vancouver, meanwhile, has won two in a row following a four-game losing streak, but still sits eight points adrift of a playoff position in the West.

"With a team like this, it was up to us to get that extra goal or be a little tighter in our own end at the start of the third," Ottawa defenceman Mark Methot said in a sombre Senators locker-room. "You've got to demoralize a team that's in the kind of position that they're in and we didn't do that."

Trailing 3-2 after two periods, Vancouver evened things up at 4:01 of the third when Bartkowski blasted his fifth of the season past Anderson on a goal that stood after a lengthy Ottawa coach's challenge for offside.

The Canucks continued to push, and Virtanen gave his team the lead at 10:59 on the power play when the rookie swatted a loose puck past Anderson for his fifth.

"We had lots of guys chipping in," said Vancouver head coach Willie Desjardins, whose team picked up just its third win of the season when trailing after 40 minutes. "The guys were pretty determined."

Mika Zibanejad rang a shot off the crossbar with under four minutes to go for the Senators, but Etem scored his second of the night and third of the year into an empty net with under 30 seconds on the clock to seal it.

"Shouldn't be in that situation," said Stone. "We gave ourselves a chance to tie - one goal post, a couple of 2-on-1s and a couple of good looks in low, but it should never be there."

Tied 1-1 after Hoffman and Etem scored in the first, the teams traded chances in the second before Ottawa grabbed a 2-1 lead 6:58 into the period when Stone buried his 20th of the season on a short-handed 2-on-1 rush.

The Canucks got that one back just 1:23 later when Bartkowski's shot through traffic appeared to go off a Senators stick and found its way past Anderson.

Ottawa restored the lead with 2:35 remaining in the period when Methot stepped around Etem with the teams playing 4-on-4 and fed Ryan, who ripped his 21st past Miller to make it 3-2.

The Senators looked to be in good shape, but a costly third would deal their post-season hopes a significant blow.

"It's very frustrating," said Stone. "We had a one-goal lead on the road, can't ask for much more."

Notes: Hoffman's goal was his 25th of the season. ... Vancouver forward Markus Granlund suited up for the first time with his new team following Tuesday's trade with Calgary that sent former first-round pick Hunter Shinkaruk the other way. ... Ottawa visits the Flames on Saturday, while Vancouver hosts the San Jose Sharks on Sunday.