New York's Thomas Greiss stopped a penalty shot in overtime to keep the game tied, and the Islanders and Florida Panthers were knotted at 1-1 after 80 minutes of play in Game 5 of their Eastern Conference quarterfinal series Friday night.

Greiss stopped 39 shots in the first 80 minutes. Roberto Luongo had 35 saves after four periods for Florida.

Frans Nielsen scored in the first period for the Islanders, and Aleksander Barkov tied it early in the third for the Panthers. The series is tied 2-2.

The Islanders' Calvin De Haan was called for closing his hand on the puck in the crease 7:19 into overtime, giving Barkov a chance to win it on a penalty shot — just the third in NHL playoff history.

But his backhander was easily handled by Greiss, and play continued.

It was the second overtime game of the series, the other being New York's home win in Game 3. Exclude Florida's empty-net goal that sealed Game 2, and all five games of this matchup between 100-plus-point regular-season clubs has been of the one-goal variety.

Florida tied it 1:59 into the third, Barkov scoring on a play kept alive by Jaromir Jagr — and one that survived a challenge from Islanders coach Jack Capuano as well.

Jonathan Huberdeau got knocked down in the left circle for what looked like it would become a giveaway. But Jagr retrieved the puck, played it back toward the right point, and Barkov scored off Alex Petrovic's pass to knot the game at 1-1. Capuano thought the play was offside, and replays showed it was extremely close but the goal held up.

The Islanders hadn't led for any part of a first or second period in the first four games of the series — and came into Game 5 having led for only 6.9 percent of the time that elapsed in the first four games, total.

That changed relatively early in Game 5.

Nielsen put New York on top with 6:29 left in the opening period. He started the eventual goal sequence with a shot from above the right circle that Luongo stopped. Thomas Hickey controlled the rebound, Luongo made another save — but the second rebound went right to Nielsen, who put home his third goal of the series.

It was a good sign for the Islanders. Nielsen also scored in Games 1 and 3, and New York prevailed both times.

For a long while, it looked like 1-0 would hold up. Greiss was brilliant time and again, his best save possibly coming midway through the second when he stoned a wide-open Aaron Ekblad from close range. Greiss stopped his first 26 shots of the night, giving him 71 saves in a 73-shot span going back to midway through Game 3.

Then Florida tied it, and eventually overtime would await.

NOTES: Neither of the other two OT penalty shots — by Joe Juneau for Washington against Pittsburgh in 1996 and Aleksey Morozov for Pittsburgh against Montreal in 1998 — turned into goals. Jagr also played in both of those games. ... Tampa Bay awaits either the Islanders or Panthers in the second round, that series set to start sometime next week. The Lightning finished off Detroit on Thursday; Florida would have home-ice over Tampa Bay, while the Lightning would host Game 1 if the Islanders advance. ... C Vincent Trocheck (foot) returned from injury to make his postseason debut for Florida. He missed 10 games in all, last playing on March 29. ... D Marek Zidlicky made his series debut for the Islanders, replacing the injured Ryan Pulock. ... Former world heavyweight boxing champion Michael Moorer was at the game. ... Attendance was 20,247, the first Florida home sellout of the series.