Dominik Simon and Evgeni Malkin each scored a power-play goal for the Penguins (6-2-3), and Matt Murray made 24 saves. Malkin extended his point streak to nine games (six goals, 11 assists).
The Penguins have lost back-to-back games since winning four in a row and getting at least a point in seven straight (5-0-2), but coach Mike Sullivan was more pleased with the effort Thursday than he was Tuesday, when defensive breakdowns cost the Penguins.
"It was a lot better," Sullivan said. "The quality of the chances that we gave up weren't nearly as high and as a result the score was down. We did a much better job in that regard."
Simon gave the Penguins a 1-0 lead at 6:20 of the first period. He followed Jake Guentzel to the slot and put the puck into the top left corner after it came to him off Greiss' right pad.
Simon has at least one point in five straight games (two goals, four assists), including a goal in the past two.
"That's a great goal on the power play," Sullivan said. "He stayed with it. To get his stick on the puck in that situation was a real nice goal. … We really like how he's tracking."
The Islanders tied it 1-1 on Bailey's shorthanded breakaway at 14:46 of the second period. He got free behind Letang and got the puck on a bank pass off the right-wing wall from Casey Cizikas. Bailey beat Murray five-hole for his third goal of the season.