Aleksander Barkov, Mike Matheson and Dominic Toninato also scored for Florida, and Sergei Bobrovsky stopped 29 shots in his sixth straight start. Jonathan Huberdeau had four assists, giving him 400 career points in 500 NHL games.
Acciari was moved up to the second line with Huberdeau and Vincent Trocheck and made the most of his opportunity.
“Those guys are very skilled guys and it was fun to play with them,” Acciari said. “Just get to the net and good things happen, and those guys found me in the right spot. It was a really exciting night.”
Artem Anisimov scored for the Senators, who have lost eight of their past 11 games. Anders Nilsson made 25 saves.
“You can’t have lapses and you can’t give them layups and that’s what we did in front of (Nilsson) tonight,” coach D.J. Smith said. “We’ll be better tomorrow.”
Acciari made it 2-0 when he took a pass from Huberdeau to the left of the crease and poked the puck into the open net early in the second for his first multigoal game.
“It was just a night that was working for our line,” Huberdeau said. “The second period sometimes we have some letdowns, so it was really good to get a lot of goals then and after that in the third period we kind of shut down a little bit. It was a good team win.”
The Senators closed to 2-1 when Anisimov got a deflected puck and put it high into the net at 2:05.
Barkov’s 11th goal, a tap-in from in front, made it 3-1 at 5:41. The score stopped a 0-for-10 drought for the Panthers on the power play.
Acciari then completed his hat trick when he poked in a rebound at 10:33.
“They were better than us all around the ice, and they deserved that win more than us,” Senators center Jean-Gabriel Pageau said. “We can’t feel sorry for ourselves. We have to come back out tomorrow and give it 110%.”
Matheson took a pass from Huberdeau near the goal line out to the left circle and fired the puck past Nilsson to make it 5-1 at 15:06.
Toninato tacked on his third of the season with 32 seconds left in the second.
NOTES: Panthers C Brian Boyle was a late scratch with an upper-body injury. … Senators D Nikita Zaitsev was sidelined by a lower-body injury.
Senators: Visit the Tampa Bay Lightning on Tuesday.
Panthers: Host the Dallas Stars on Friday.
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