Hunwick jumped up to join the play and created an odd-man situation for Pittsburgh that led to the winning goal.
''I saw one of their guys changing, so it was a chance to create a 3-on-2,'' Hunwick said after his first NHL overtime goal. ''You hope you score there because if I had to go back down the ice and play defense again, I'd probably be pretty tired.''
Pittsburgh led 3-1 in the third period, but the Islanders tied it with goals in the final 4:53. Hunwick salvaged a victory with his third of the season by pushing one in during a scramble in front of the net, created by Bryan Rust's initial drive to the goal.
''(Rust) just got it to the net and I was able to bang in the rebound,'' Hunwick said.
Phil Kessel got his team-leading 14th goal on a power play, and Jake Guentzel and Riley Sheahan also scored for Pittsburgh. Rookie Tristan Jarry made 23 saves for the Penguins, who have won five of six since a three-game losing streak.
Jaroslav Halak stopped 28 shots for New York, which has lost three of four since a four-game winning streak.
The Islanders nearly won for the ninth time in 12 games, but Jarry made a stick save on Josh Bailey during a breakaway in overtime.
''It was a good road game,'' Eberle said. ''Going into the third with a 1-1 game, they make it 3-1 and we battled back. It was a weird game in that aspect, but I guess you can salvage a point and be happy about that.''
Kessel and Sheahan scored 32 seconds apart midway through the third period, briefly giving Pittsburgh a 3-1 lead. Kessel sent a wrist shot over Halak's glove and into the top corner from the left faceoff dot 7:29 into the period. Soon after, Halak left his crease but misplayed a clearing attempt, allowing Sheahan to take advantage. Sheahan found the top corner, beating Halak to the blocker side with a wrist shot for a goal on his 26th birthday.
But the Islanders rallied.
Barzal beat Jarry with a wrist shot from the slot, and then Nelson tied it. Thomas Hickey put the initial shot on goal, and Nelson converted the rebound from atop the crease.
The Penguins and Islanders both played without top defensemen. Pittsburgh's Justin Schultz was placed on injured reserve and is expected to miss a couple weeks with a lower-body injury. Johnny Boychuk missed for the Islanders with a lingering undisclosed injury that isn't believed to be serious.
Guentzel opened the scoring with a power-play goal, tipping Kris Letang's point shot behind Halak. The Penguins have at least one power-play goal in seven of their last eight games. The Islanders have allowed 13 power-play goals in their last nine games.
NOTES: Penguins F Tom Kuhnhackl left in the third period and didn't return following a collision with teammate Ryan Reaves. ... Penguins G Matt Murray skated in full pads and took shots from goalie coach Mike Buckley before the morning skate. Murray missed his fourth game with a lower-body injury. ... Kessel has a point in 23 of 30 games for Pittsburgh this season. ... Penguins F Sidney Crosby has at least one point in nine of his last 11 games, while Evgeni Malkin has points in all four games since missing four games with an upper-body injury. They each had one assist Thursday. ... Casey Cizikas returned for the Islanders after missing four games with a lower-body injury. He replaced Alan Quine in the lineup at fourth-line center. ... Penguins D Frank Corrado, who was recalled for Schultz, was scratched.
Islanders: Conclude a four-game road trip Saturday night at Boston
Penguins: Continue a season-long five-game homestand Saturday night against Toronto
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