Sillinger scored with 26.8 seconds remaining in regulation time as the New York Islanders rallied for a 6-5 victory over Pittsburgh, ending the Penguins' point streak at 16 games. Sillinger took a pass from Andy Hilbert in the high slot and got off a shot that hit under Marc-Andre Fleury's glove and carried in for his 20th goal. New York, 2-1 on its seven-game homestand, rebounded from a shutout loss to New Jersey on Saturday.
"We found a way to win," Sillinger said. "When you outscore a team like this, you're doing something right."
Pittsburgh, riding a 14-0-2 surge that vaulted the Penguins from also-ran to Atlantic Division-contenders, got three goals from Ryan Malone, two from Mark Recchi and four assists from NHL scoring leader Sidney Crosby, but couldn't survive shaky goaltending by Fleury.
He will have to be better if the Penguins hope to reach the playoffs for the first time since 2001.
"Guys in here are disappointed and upset, and that's a good thing," said Recchi, who added three assists. "We played three hockey games in such a short time, and to see people unhappy after losing the third one is a good sign."
Crosby nearly set up another goal seconds earlier, but couldn't escape Trent Hunter behind the net.
"When you score five goals on the road, you've got to win those games," Penguins coach Michel Therrien said.
Chris Simon scored twice, Viktor Kozlov, Jason Blake and Miroslav Satan added goals, and Marc-Andre Bergeron had two assists in his Islanders debut one day after being acquired from Edmonton.
"We weren't worried about their streak or anything, we were just kind of worried about ourselves," forward Arron Asham said.
Pittsburgh, which led 3-1 and 5-4, hadn't lost in regulation since Jan. 10 at Florida. It was the Penguins' longest streak since an 18-game run in 1993 that included a league-record 17 consecutive wins.
"Losing is never fun, but it was going to happen sometime," said Crosby, who has three goals and 14 assists against the Islanders. "Mentally, it's tough to go through something like that and come up short."
Malone scored in the opening minute of all three periods, but the Penguins continued a recent pattern of blown leads and had a six-game winning streak broken.
"This was a tough one to lose," Malone said. "We didn't want to give one up in the last minute.
"We can't be giving up three, four, five goals every game."
Crosby is first in the league with 95 points, despite only one goal in 11 games. He has multi-point games in all six contests against New York this season, and his 31 career points in two seasons are his most against any team.
Malone gave Pittsburgh a 5-4 lead at 48 seconds of the third, putting in his rebound after a shot from Crosby bounced to him. He has 12 goals this season, six against the Islanders in the first two hat tricks of his career.
Simon broke out of a 26-game scoring drought, netting his second of the game and seventh overall 1:11 later.
Pittsburgh, which boasts the NHL's second-youngest roster, showed no signs of fatigue early in its third game in four days.
Crosby handled the puck near the right post and backhanded a shot into traffic that hit Recchi and popped up. Malone reached to glove the puck, knocked it down to his stick, and shot it past Rick DiPietro.
Recchi notched his 21st goal, one day after reaching 20 for the 15th time in 18 seasons. The power-play goal gave Pittsburgh a 2-1 lead with 49 seconds left in the first.
The Penguins needed only 49 more at the start of the second to grab a two-goal advantage. After a lengthy video review, Malone was credited with his second of the game and fifth against New York this season.
Their joy was short-lived as the Islanders tied it with goals by Simon and Blake 15 seconds apart. Simon made it 3-2 at 2:03, then, during a delayed-penalty call, Blake tied his career high with No. 28.
It marked the fourth time in six games that the Penguins blew an advantage of at least two goals, but they had all won the others.
Satan gave New York its first lead at 8:05 when he put in a juicy rebound after a hard drive by Kozlov with four skaters aside. Fleury, who took Sunday off against Washington after starting 14 of 15 games, has given up at least four goals in seven of nine outings.
"Lately, we've given him four, five goals a game," Therrien said. "His last four games in a row, he's not been good enough."
Recchi struck again 16 seconds into a 5-on-3 advantage, making it 4-4 with 1:59 remaining in the second.
Kozlov's power-play goal 14:49 into the game tied it 1-1 and was New York's second with a man advantage in 22 chances over eight games.
Notes: Malone scored three goals against New York on Dec. 15 . . . Crosby has 30 career points against Philadelphia . . . Malone is the eighth Penguins player to reach 10 goals . . . DiPietro, who took a roughing minor in the middle period, is second among NHL goalies with 20 penalty minutes.