The 27-year-old Swede made 28 saves for his second shutout of the season as Vancouver downed the Arizona Coyotes 5-0 on Thursday as Ryan Miller dressed as the backup after missing 21 games with a knee injury.
The Canucks have yet to name a starting goalie for the post-season, but it's hard to imagine a scenario where Lack — who is 12-6-2 with a .927 save percentage since Miller went down on Feb. 22 — doesn't get the call.
"I've always stuck to my own business and worked hard," said Lack. "I've always thought that if I keep working hard my chance is going to come eventually. But playing such a big role in the playoff hunt, I didn't expect that."
Yannick Weber scored twice and Daniel Sedin, Ronalds Kenins and Dan Hamhuis had the other goals for Vancouver (47-29-5), which clinched a playoff spot Tuesday without even suiting up when the Edmonton Oilers downed the Los Angeles Kings 4-2.
Alexander Edler added three assists, while Henrik Sedin chipped in with two of his own for the Canucks, who missed the post-season in 2013-14 for the first time in six years, but have rebounded under rookie head coach Willie Desjardins.
Depending on what the Calgary Flames do in their finale Saturday afternoon against the Winnipeg Jets, the Canucks still might need a victory in their game later that evening at Rogers Arena against Edmonton to lock up second place in the Pacific Division and home ice advantage in the first round.
The Flames beat the Kings 3-1 on Thursday to secure a post-season berth and guarantee an all-Canadian opening-round matchup against the Canucks.
On the Vancouver goaltending front, Desjardins did give a strong indication that Miller would start against Edmonton.
"You have to have two goalies going into the playoffs," said the coach. "It would be tough on Ryan if he ended up playing in the playoffs without having played in so long."
Lack, who picked up the sixth shutout of his career, has played 22 of 23 games since Miller went down, but was rarely tested against lowly Arizona.
Fans saluted Lack with chants of "Eddie! Eddie!" after a couple of saves on an Arizona power play midway through the third period, his busiest sequence of the night.
"We've had a connection from the start, me and the fans," said Lack. "It's been a fun ride and they're going to be a big part of any playoff success."
Mike Smith allowed four goals on 24 shots before getting pulled late in the second period for the Coyotes (24-49-8), who will finish their miserable season on Saturday at home against the Anaheim Ducks.
Louis Domingue finished with seven saves in relief for the Coyotes, who are second last in the overall standings and can still finish below the Buffalo Sabres in the race to pick Connor McDavid first overall at June's NHL draft.
"Poor execution, some penalties we couldn't kill and we chased the game," said Coyotes head coach Dave Tippett, whose team gave up three power-play goals.
Vancouver opened the scoring with 3:38 left in the first when Daniel Sedin's off-speed shot knuckled its way past Smith for his 19th of the season. After Kenins doubled that edge 6:51 into the second with his first in 22 games, Weber blasted his 10th and 11th goals of the season on one-timers from almost exactly the same spot. The first came on a 5-on-3 power play at 15:42 before Weber fired home his second on the subsequent 5-on-4 advantage just 1:28 later.
Hamhuis rounded out the scoring with his first of the season on another power play with 3:11 to go in the third.
The Canucks know they can't look past the Oilers on Saturday, but Henrik Sedin took a moment to reflect on the last time Vancouver played Calgary in the playoffs back in 2004 — a series the Flames won in seven games.
"It was a tough series. I think we were the favourites," he said. "Two good teams. Big rivalry. To play in the Saddledome with the fans they have there and the sea of red and everything, I think for the young guys it's going to be amazing."
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