Jonathan Huberdeau got the 500th point of his career for Florida, while Anthony Duclair and Aleksander Barkov added goals for the Panthers.
Oliver Wahlstrom scored for the Islanders, his power-play goal 3:30 into the third getting New York within 3-1.
But Bennett got his third of the night midway through the final period, then Barkov made it 5-1 with his first of the season.
Ilya Sorokin stopped 24 shots for the Islanders, who have been outscored 11-4 this season and failed to get a point out of their first two games for only the second time in the last 15 years. It also happened in 2016-17.
Florida is off to a 2-0-0 start for just the seventh time in the franchise’s 28 seasons.
Bennett’s other hat trick was actually a four-goal game — against Florida, for Calgary on Jan. 13, 2016. It was the 55th hat trick in Florida history, with 32 Panthers now having at least one.
The Panthers have three different players with at least a two-goal game already this season. That’s never happened before in team history; there had been two different two-goal scorers in the first two games of a season on four other occasions.
Carter Verhaeghe and Aaron Ekblad had the two-goal contests in Thursday’s opener. Bennett joined them Saturday, getting his first when the puck bounced through the crease onto his stick, and he tapped it into wide-open netting for a 1-0 lead in the first period.
The second one took a little more effort; he scored on a wraparound on the play where Huberdeau had an assist for his milestone point.
Duclair got his second of the season on a breakaway late in the second, and Bennett’s third of the night came on a shot from the slot that bounced off Sorokin.
The game was the 98th pitting Florida’s Joel Quenneville against the Islanders’ Barry Trotz.
Including 11 playoff meetings, Quenneville’s teams — Florida, Colorado, Chicago and St. Louis — have won 51 times. Trotz’s teams — the Islanders, Washington and Nashville — have won 44 times.
There were three ties, the last of those coming in 2002, two years before ties no longer became possible in NHL games.
Florida has now won only two of the last nine meetings against the Islanders. The teams last played in August 2020, when New York ousted the Panthers in the qualifying round for that season’s playoffs, the Isles winning the best-of-five 3-1. … This was the first of two visits to Florida for the Islanders on this “trip.” Their 13-game road stretch to start the season ends when they visit the Panthers again on Nov. 16; the Islanders’ home debut at the new UBS Arena in Elmont, New York comes on Nov. 20 against Calgary.
Islanders: Visit Chicago on Tuesday.
Panthers: Visit Tampa Bay on Tuesday.