Nursing a three-goal lead in the third period, the Islanders got quite a jolt when the Panthers rallied to tie it with three goals in less than two minutes.
But Casey Cizikas broke that tie, and the Islanders held on to beat the Panthers 4-3 on Saturday night.
"We take five, 10 minutes off and you kind of lose focus. That's what happens," Cizikas said. "It's just a perfect example of how you have to play a full 60 minutes. It's something that we can learn from."
"Mac made a great play behind the net of finding me right there," Cizikas said. "I just tried to get it off as quick as possible."
New York also jumped ahead of the rival New York Rangers into ninth place in the Eastern Conference.
T.J. Brennan, Marcel Goc and Mike Santorelli scored in a span of 1:43 of the third to tie the game. Scott Clemmensen made 21 saves, but Florida lost its sixth straight and for the ninth time in 10 games.
This is the Panthers' longest skid since they were 0-7-3 from March 19-April 8, 2011.
The Panthers staged a spirited comeback and scored three goals in a flash. Brennan, playing his first game since being acquired from Buffalo on Thursday, grabbed a loose puck in front of the Islanders net and swept it in at 5:09 to make it 3-1.
"I just tried to throw one to the net and hung around," Brennan said. "The puck kind of popped out, and I threw it on net. The next thing I know it's in and guys are celebrating.
"We got a little momentum off of that."
Goc scored 34 seconds later when he one-timed a pass from Jack Skille, and Santorelli tied it 1:09 after Goc's goal at 6:52.
"We threw a lot of energy out there and we finally got some production for the effort we were putting in," Panthers coach Kevin Dineen said. "I like that we came back and we pushed that hard. It made our team very emotional in a positive way."
The Islanders were able to respond when they needed to and scored last to win it.
"I knew they'd make a push," Islanders coach Jack Capuano said of the Panthers. "But we found a way to get it done. We called a timeout, raised our battle level to where it needed to be and we got a big goal from a line that worked extremely hard."
McDonald's assist on the final goal capped off a wild week for him. He missed Thursday's game due to a stomach flu that kept him bedridden. On Friday, he signed a two-year, $1.275 million extension.
"It was a bit of a whirlwind, but it was just a great end to a week that I'll definitely never forget," McDonald said.
The Islanders led 2-0 after the first period. The Panthers have given up the first goal in each of their past six games and are 1-14-4 when their opponent scores first.
New York went ahead 1-0 on Okposo's goal. Frans Nielsen passed from behind the net out to Okposo in front. His slap shot beat Clemmensen at 15:56.
The Islanders doubled their advantage when Martinek took a shot from about 15 feet inside the blue line that got past Clemmensen at 17:59.
The Islanders stretched their lead to 3-0 on Boyes' goal 33 seconds into the second period. His shot from below the right circle glanced off the skate of Florida's Tomas Kopecky and went into the net.
Panthers defenseman Ed Jovanovski returned after missing 22 games because of a lower-body injury but left the game after the second period and didn't return. His condition will be updated Monday, Dineen said.
Panthers forward George Parros left the game with an upper body injury in the first. He fought with Eric Boulton and got slammed hard into the ice. ... Brennan was acquired from Buffalo for a fifth-round pick in this year's draft.