Andrej Meszaros and Scott Hartnell also scored for Philadelphia, which snapped a two-game skid and handed the Islanders their eighth loss in ten games.
Kyle Okposo scored his first two goals of the season and Michael Grabner scored for New York. Okposo's first goal ended the Islanders scoreless drought at 142 minutes, 17 seconds.
New York entered the game having been outscored 20-13 in the first period. At the first intermission, though, it was the Islanders who held a 3-1 advantage thanks to Okposo's two goals and Grabner's first goal since November 10.
Okposo tied the game 1-1 season 19 seconds after Meszaros scored with a wrist shot over Ilya Bryzgalov's glove. Okposo's second goal of the game at 10:26 made it 2-1. He tapped a centering feed from Josh Bailey to complete a power-play passing sequence.
Grabner's wrist shot at 18:29 from the left faceoff circle increased the Islanders' lead to 3-1.
Peter Laviolette replaced Bryzgalov, who turned away six of nine shots, with Sergei Bobrovsky before the start of the second period. Bobrovsky made 23 saves, including stops on breakaways for Matt Moulson and John Tavares midway through the second period.
Islanders coach Jack Capuano announced that DiPietro would start in goal before the Islanders' morning skate. DiPietro had not played since the first period of Saturday's 6-0 loss to Boston, in which he had allowed three goals on 13 shots in that game before being replaced by Anders Nilsson.
DiPietro made 29 saves in an adventurous effort. He yielded Meszaros' off-the-rush slapshot 18 seconds into the game, Hartnell's ninth of the year 5:25 into the second period on the power play, Briere's in-tight wrister that tied it 3-all with 5:42 left and Brier's winner.
The Islanders called up Michael Haley from AHL Bridgeport on Monday, hoping hte tough guy would spark the team after several weeks of uninspired play.
Haley, who recorded 39 penalty minutes and scored a goal in New York's 9-3 brawl-marred win over Pittsburgh on February 11, had three points (a goal and an assist) along with 32 penalty minutes for the Sound Tigers this season.
NOTES: The Islanders have lost 13 of 16. ... TSN reported Monday night that New York left wing Blake Comeau is on the trade market as he had not recorded a point in 15 games. "It's the way it is sometimes in this business. You hear things, but, for me, personally, I'm not too focused on it at all," Comeau said after the morning skate Wednesday. . The Flyers left for Philadelphia directly after the game. They host Montreal Friday afternoon and play their long-time Atlantic Division rival, and Winter Classic opponent, the Rangers in the refurbished Madison Square Garden Saturday afternoon. .New York debuted their new black jerseys. They will wear the new jerseys 11 more times this season. . Philadelphia right wing Jaromir Jagr only played 7:52 spanning the first two periods because of a lower body injury. He was minus-two. . The announced attendance was 11,086 although there were large swaths of empty seats.