PITTSBURGH -- John Taveras' goal early in the third period lifted the New York Islanders to a 3-1 victory over the Penguins on Friday night as Pittsburgh again failed to lock down a playoff berth with its fifth straight loss.

The Penguins (43-26-12) need two points against the Sabres -- whose 23-49-8 record is the worst in the NHL -- on Saturday night at Buffalo or will miss the playoffs for the first time since the 2005-06 season.

Despite being 4-7-2 in their last 13 games, the Islanders (47-28-6) are headed to the playoffs. They clinched a playoff spot Thursday despite being off when the Boston Bruins lost to the Florida Panthers.

The Islanders are now assured of finishing third in the Metropolitan Division and will face the Washington Capitals in a first-round series in the Eastern Conference.

Taveras scored his 37th goal with 17:14 remaining to break a 1-1 tie, converting a rebound when right winger Kyle Okposo's shot from the blue line caromed off goaltender Marc-Andre Fleury's left pad.

With two days left in the season, Taveras and Penguins center Sidney Crosby are tied for the league lead with 84 points. The Dallas Stars' Jamie Benn has 83.

Left winger Michael Grabner added a goal, his eighth, on an end-to-end rush, with 3:40 remaining to pad the Islanders' lead to 3-1. The Consol Center crowd then spent the game's final minutes booing the fading Penguins.

Center Casey Cizikas also scored as the Islanders won for just the fourth time in their last 22 games in Pittsburgh. Goaltender Jaroslav Halak stopped 37 shots.

Defenseman Rob Scuderi scored the Penguins' lone goal in the dying moment of the second period, his first in over two years.

NOTES: Islanders LW Matt Martin and C Frans Nielsen both missed the game with undisclosed injuries. While Nielsen was with the team, Martin remained back in New York. ... Islanders RW Cal Clutterbuck returned to action after sitting out Tuesday's loss at Philadelphia, also because of an undisclosed injury as New York is playing it close to the vest regarding its players' health. ... Pittsburgh was left with just five defenseman as D Christian Ehrhoff and D Derrick Pouliot both sat out with upper-body injuries. ... Penguins LW Chris Spaling was in the lineup despite suffering a lower-body injury that forced him out of Tuesday's loss at Ottawa.