Getting swept in a home-and-home series by one of the East's afterthoughts has just about torpedoed the Penguins' chance of finishing atop the conference.

Now, Pittsburgh must worry about entering the postseason without momentum. Its task gets no easier tonight as the club faces the Buffalo Sabres, who are riding their longest winning streak of the season in a desperate attempt to make the playoffs.

The Penguins placed pressure on the Atlantic Division and East-leading Rangers by putting together a 13-0-1 spurt from Feb. 21-March 22 and also got captain Sidney Crosby back into the mix over that time. However, Pittsburgh has gone 1-3-0 over its last four trips to the ice and was just swept in a home-and- home series by the 13th-place Islanders this week.

Pittsburgh dropped a 5-3 decision at home to New York on Tuesday, then lost by the same score two nights later on Long Island. That leaves the Penguins five points back of the first-place Rangers with five games left to play. The Rangers are also in action tonight, hosting Montreal.

The Penguins also have to keep an eye on the fifth-place Flyers, who pulled within two points of Pittsburgh for the East's fourth seed with their win on Thursday. Philadelphia is idle tonight and the two clubs will clash in a big meeting on Sunday in Pittsburgh.

"We've got to worry about our game. The standings will be the standings," said Pittsburgh's Jordan Staal, who had a goal. "We want to win games and right now we're not playing our best hockey and we're losing."

Evgeni Malkin added his 47th goal and league-leading 100th point of the season in last night's loss, while Pascal Dupuis lit the lamp to stretch his point streak to 12 straight games. He has nine goals and six assists over that span.

Marc-Andre Fleury gave up four goals on 23 shots for the Pens, who have lost consecutive games for the first time since Feb. 5-7 and are in danger of losing three in a row in regulation for the first time since an 0-6-0 drought from Dec. 29-Jan. 11.

Pittsburgh also got a scare in the second period when Crosby exited after getting hit in the face by a puck. The center has missed much of this season due to concussion-like symptoms and a neck ailment, but was able to return and finish out the game.

The Penguins could certainly use Crosby as they take on a Sabres team that has won a season-high five straight and have gone 7-0-2 in their past nine. Buffalo's 5-1 win over Washington on Tuesday gave the Sabres a two-point edge over the Capitals for the eighth and final playoff spot in the East, but the Caps picked up two points in last night's win over the Bruins.

Still, Buffalo holds the current tiebreaker between the clubs with five games left in the season compared to Washington's four and will use that game in hand tonight.

Drew Stafford scored twice in Tuesday's win at Washington, while Ryan Miller made 44 saves. Thomas Vanek, Jason Pominville and Cody McCormick also lit the lamp for the Sabres, who sat 14th overall in the East on Feb. 17 but have gone 14-2-4 since.

"Every game been a must-win for us, obviously, with this game [and the Capitals] being right with us in the standings, the stakes are a little bit higher, but we're not done yet," Stafford said. "We're in the position we want to be in but we know the road's going to get even tougher."

The Sabres are on their longest winning streak since picking up six straight wins from Dec. 29-Jan. 8 during the 2009-10 campaign, but will look to match that run tonight without defenseman Christian Ehrhoff. The blueliner left Tuesday's victory in the first period with a knee injury that will cost him some games.

The Sabres have won two of three over the Penguins this season and answered an 8-3 loss at Pittsburgh in December with a 6-2 victory over the Pens at home on Feb. 19.

Pittsburgh has won seven of its last nine overall versus Buffalo and seven of its past 10 trips to western New York. Malkin has three goals and six points in two games versus the Sabres this season.