The combination has put the West's first wild card a win away from reaching the second round.
Radulov scored two goals in the second period and the Stars beat the Nashville Predators 5-3 on Saturday to push the Western Conference's No. 2 seed to the brink of elimination.
The Stars now lead this best-of-seven series 3-2 over the two-time defending Central Division champs. Dallas will have a chance Monday night at home in Game 6 to join Colorado and Columbus as the latest lower seed coming through in the opening round.
"I think we keep getting better, and we have to keep getting better," Dallas coach Jim Montgomery said. "The next one's the hardest one because it's the potential to end someone's season. That's the challenge in front of us now."
Jason Dickinson also scored twice, Seguin had a goal and an assist, and Benn matched the NHL playoff record for most assists in a single period with three in the second. The Stars also scored at least five goals in back-to-back playoff games for the ninth time in franchise history, the first since Games 3 and 4 of the 1991 conference finals when this team was still in Minnesota.
Ben Bishop, named a finalist for the Vezina Trophy during the game, made 30 saves for the win.
"It's a great honor," Bishop said of being a finalist. "As much as it is an individual award, it's a team thing. The guys have done a great job in front of me all season."
Rocco Grimaldi, Ryan Johansen and Kyle Turris scored for Nashville. The Predators lost back-to-back playoff games for the first time since Games 5 and 6 of the 2017 Stanley Cup Final. Nashville coach Peter Laviolette said his Predators have been in these situations before.
"They've answered the bell," Laviolette said. "They'll answer the bell in Game 6 and we'll bring it back here."
Laviolette got forward Brian Boyle back after missing the past three games with an appendectomy and mixed up his lines. Nashville struggled too much with sloppy play including 19 giveaways.
Credit Dallas' top line for making the Predators pay for those mistakes. Seguin, Benn and Radulov took 16 of the Stars' 26 shots, and the trio was responsible for all three goals in the second. Montgomery said Benn was banging his stick wanting more ice time for the line, and Seguin said that line is all about work and will.
"Obviously, we have the skill and talent there," Seguin said. "When we're working hard, we're happy to go up against anybody. They're a good team. They had some good pushbacks tonight. I think goalie still played really good, especially early on. It's going to be a really hard game to try and win on home ice."
Grimaldi has been Nashville's most surprising scorer in this series, and he gave them a 1-0 lead at 6:25 with a wrister over Bishop's glove. Then Rinne came through with a pair of dazzling saves while on his back 70 seconds later, stopping a backhander from Radulov with his left leg and then a shot from Benn with his left.
Dickinson tied it up for Dallas at 13:08 of the first, beating Rinne with a wrister for his first goal this postseason.
The Stars seized control in the second.
The Predators failed to clear the puck after winning a faceoff, and Seguin passed to Radulov who scored his third this series into an open net with Rinne at the far post just 40 seconds into the second period for a 2-1 lead. Radulov gave Dallas a 3-1 lead with a goal from the slot off a backhanded pass from Benn at 7:41 with the Stars fully in control. Benn beat Nashville defenseman Ryan Ellis to the puck to pass to Radulov.
"It's a race for the puck and you just want to do whatever you can to get that puck," Benn said. "I heard those guys calling behind me way before I had the puck because they always want the puck. I just found a way to get it to Rads there and he made a great shot."
Johansen scored his first goal this postseason at 9:18 off a pass from Filip Forsberg. Dallas simply made it a 4-2 lead as the Stars caught Nashville in a line change, and Benn passed to Seguin in the slot who slid the puck under Rinne's left pad at 15:54.
Rinne said the Predators have to get better.
"It's not good enough," Rinne said.
Dickinson made it 5-2 with a slap shot from the high slot off another Nashville turnover at 1:57 of the third. Turris was credited with a goal at 2:25 where the puck went off Stars defenseman Miro Heiskanen's skate.
NOTES: Nashville came into this postseason one of only three teams to reach the second round each of the past three seasons with Washington and Pittsburgh, and the Penguins were swept in the first round. ... Radulov posted his second multi-goal performance in the playoffs. His last was in Game 1 of the 2007 conference quarterfinals with Nashville. ... Washington's John Carlson also had three assists in a single period in Game 1 against Carolina this postseason. ... Grimaldi scored only five goals in 53 games during the regular season.
The Stars can end the series Monday night in Game 6 in Dallas.
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