The unexpected score allowed the Nashville Predators to tie the game early in the third period Friday night and changed the momentum in their direction.
Dumont wasn't through, however. He finished off his impressive final period with the go-ahead score and the Predators added two empty-netters to beat the Blackhawks 4-1 for their first-ever road playoff victory.
"It was a lucky bounce, but we'll take it," said Dumont, who played for the Blackhawks a decade ago. "That's what happened; we had been working really hard down low. That was definitely a good bounce for us."
It was Nashville's first road playoff win in 11 tries. Now they'll try for another in Game 2 on Sunday night at the United Center.
"It definitely was huge. We have a lot of guys who played their first playoff game tonight, and playing Chicago and the anthem was so loud in the building, we could have been intimidated," Dumont said.
"But we were pretty much relaxed out there and just played our game."
Pekka Rinne made 25 saves in his playoff debut for the Predators, allowing only Patrick Kane's second-period goal. After Dumont gave Nashville a 2-1 lead, Jerred Smithson and Martin Erat added empty-net goals in the final 48 seconds.
Nashville's David Legwand got the puck after a turnover by Chicago's Troy Brouwer, raced in and took a shot that Niemi stopped, but Dumont was there to knock in the rebound to give the Predators a 2-1 lead at 10:37 of the final period.
But it was Dumont's first goal that really seemed to sink the Blackhawks. He just put it on net from deep on the right side and somehow it went in.
"It definitely gave us a little jump. It was only 1-0 and we were playing our game, waiting for a chance," Dumont said. "You see the time running and you always get a little bit nervous. But when I came back to the bench I could see the guys were relaxed and that definitely was a good sign."
Niemi, a rookie who emerged as Chicago's top goalie with his play late in the season, made 22 saves in his playoff debut. But the first goal he allowed was one he'll long remember, especially because Dumont's shot was trickier than it was hard.
"The second goal was a tough one. It was a turnover at a critical spot," Chicago coach Joel Quenneville said. "The first goal took a funny hop and a funny bounce, but you're still in a good spot. That's why I'm not happy about the second."
When Patrick Sharp fired a shot from the left circle that went off Rinne, he couldn't control the puck and Kane was there to follow it in from right in front of the net for his 10th career playoff goal. That gave the Blackhawks a 1-0 lead midway through the second period.
Sharp had a chance to score earlier on a nice pass from Marian Hossa but his shot hit the post.
"It was important for us to get this first win on the road. It gives us a lot of momentum," Rinne said. "We played a solid game and created turnovers. We were especially strong in the third. We stayed with our plan and it worked. I got lucky on Sharp's shot, which hit the post."
Rinne made a good stop on a rebound attempt by Jonathan Toews after a shot by Hossa and later had a great poke check to thwart a breakaway attempt by Sharp in the scoreless first period.
Employing a neutral-zone trap defense to combat Chicago's puck possession game, the Predators and Blackhawks finished with 26 shots apiece. Nashville had a 13-4 advantage in the pivotal third period. Chicago led the NHL this season with an average of 34 shots per game while allowing a league-low 25.
"They're aren't too many plays where you get odd-man rushes," Kane said. "Their trap overall, we can play better against it. We've got to get the puck deep.
"Their goalie's pretty good, too."
The Blackhawks and Predators played six times in the regular season, with Chicago winning four times, but in a scheduling quirk, they hadn't met since Dec. 27.
Predators D Denis Grebeshkov, who was hurt March 7 when hit by a puck, was a scratch but could be available for Game 2. ... Attendance was 22,256. ... Dumont has 17 playoff goals in 43 games.