That's when he learned he had tied a team record with his third hat trick of the season, joining Mike Modano and Bill Guerin. Seguin also had two assists Thursday night as the Stars beat the Vancouver Canucks 6-1.
"Until I saw it on the board, I wasn't aware," he said.
He was especially pleased to be in the company of Modano, whose No. 9 will be retired at the Stars' game Saturday.
"It's awesome," Seguin said. "I talk a lot with him when he comes to game. He tells me a couple of things about my game."
Seguin, the team leader with 29 goals, has had two of the NHL's six five-point games this season.
Seguin scored twice in the first period, and completed his hat trick at 12:53 of the third by squeezing the puck through a narrow opening past Canucks backup goalie Jacob Markstrom.
Vancouver's Zac Dalpe scored at 18:15 of the second period.
Dallas solidified its hold on the eighth and final playoff spot in the Western Conference, improving to 9-3-2 in their last 14 goals.
The fading Canucks, 11th in the West, dropped to 1-10-1 in their last 12 and fell four points behind Dallas.
Vancouver coach John Tortorella said he didn't believe his team quit.
"I still think there is the people in (the locker room) that can help us pull through this and we're going to keep on going about it each day."
"It feels like we're ready when the game starts, and then we kind of just collapsed today," Lack said. "For me, I kind of just have to look at myself tonight ... and have to be better."
Benn put in a rebound 2:57 into the game after Lack had stopped Seguin's backhand.
Seguin scored the second goal on a power play. He took a pass from Alex Chiasson behind the Canucks' defence and fired into the upper right corner from in front of the net.
"That was a big message before tonight's game, was our starts," Seguin said.
The Stars had been outscored 6-0 in the first period of their previous three games.
Even at 2-0, the lead appeared safe against a team that has scored only nine goals in its last eight games.
Seguin made it 3-0 at 11:59, taking a pass off the boards from Peverley and turning and one-timing a shot between Lack and the right goal post.
"The one he rips from the wall in the first period found a way to go in," Dallas coach Lindy Ruff said. "You could just say it's never a bad play to get it on net.
"His late one, for the hat trick, you wonder how it goes in, but it went in. (Vernon Fiddler) said on the bench, 'Those never go in for me.' It is funny how sometimes goal scorers find ways to put them in the holes."
The shots on goal, eight for each team, did not reflect Dallas' domination of the first period.
The Stars began the second on a 5-minute power play. Vancouver's Zack Kassian received a major penalty for boarding and a game misconduct for a hit on Brenden Dillon in front of the Canucks' bench with 1:30 left in the first period.
With that man advantage, Dallas took a 4-0 lead at 2:20 of the second. Ray Whitney passed from behind the goal line to defenceman Goligoski low in the right faceoff circle. He shot into the near side of the net. Seguin assisted on the goal.
At 12:08, Goligoski passed across to Garbutt on the left side, and his goal increased the lead to 5-0.
Goligoski said, "We came in more focused. We knew these guys have had a tough time scoring goals, so we needed to bury a few early."
Dalpe scored a power-play goal late in the period to get the Canucks on the board with a shot that hit Lehtonen as he tried to recover his position.
The teams again were tied in shots, with nine each. Vancouver outshot Dallas 16-5 in the third period.
NOTES: Dillon left the ice after Kassian's hit, but returned for the second period. ... Goligoski has a goal in each of the last three games after scoring only twice in his first 59 games this season. "It's a case of being in the right place at the right time," he said. Dallas defencemen have totalled six goals in those three games. ... Benn has two goals and seven assists in his last six games. ... Lack, starting for the Canucks for the fifth consecutive game, had allowed 1.25 goals per game for the first four.