Brad Marchand snapped a third-period tie with his team-leading 27th goal, and the playoff-bound Boston Bruins ended the New York Islanders' minuscule postseason chances with a 6-3 victory on Saturday.

The defending Stanley Cup champion Bruins, who lead the Northeast Division, had plenty of support as a large throng of fans cheering "Let's Go Bruins" throughout while decked out in black and gold jerseys filled the Nassau Coliseum and made up about half of the sellout crowd.

Tyler Seguin, who made the pass to set up Marchand's goal 3:13 into the third, pushed Boston's lead to 4-2 with 9:23 remaining and matched Marchand with his 27th goal. Patrice Bergeron and David Krejci scored seconds apart later in the third to turn it into a rout.

Krejci had two goals, Chris Kelly also scored for Boston, and Marty Turco stopped 19 shots for his second win in four outings since coming back to the NHL and joining the Bruins earlier this month. The 36-year-old Turco was out of the NHL since last March with Chicago, and had been playing in Austria before signing with the Bruins.

Boston (46-28-4) clinched an Eastern Conference playoff spot on Friday night when the Buffalo Sabres lost. Now the Bruins are closing in on the Northeast title with four games left.

Kyle Okposo scored for the fifth straight game, and PA Parenteau had two goals for the Islanders (33-34-11), who had won five of six — including victories in their two previous games against Pittsburgh. The loss kept New York out of the playoffs for the fifth straight season.

Al Montoya made 21 saves for the Islanders.

The Bruins failed to hold a pair of one-goal leads — one in each of the first two periods, and the teams were tied 2-2 heading into the third.

Krejci got it started late in the sluggish first period that didn't produce much of anything until the final two minutes. Milan Lucic, who was serenaded by the Bruins faithful with loud chants of "Loooch!" every time he touched the puck, sent a backhanded pass from behind the Islanders net into the lower portion of the right circle. Krejci took the puck there, and one-timed a shot while going down to a knee that beat Montoya with 1:49 left in the period for his 22nd goal.

Okposo answered it just 29 seconds later with his career-best 21st goal, and sixth in five games. Frans Nielsen raced the puck up ice, easily going around former Islanders forward Brian Rolston, and rushing into the Boston end. He got the puck to Okposo, who streaked down the middle and snapped a shot past Turco at 18:40.

There were no penalties called in the first period, and the Islanders had the only two power plays in the second — a frame that featured a fight between New York's Micheal Haley and Boston counterpart Gregory Campbell.

The Islanders failed to take advantage of either power play, but still managed to get even again with 5:34 left in the second on Parenteau's first of the game.

John Tavares made the play happen with a brilliant spin move in front of Turco to shift the puck to his forehand, and move it deftly to Parenteau, who easily scored into the wide-open right side of the net.

Boston regained the lead 4:56 into the second off an Islanders giveaway in the Bruins' zone. Montoya kicked out a long rebound of Rolston's shot to Andrew MacDonald, but the defenseman's clearing attempt was intercepted by Kelly near the right point. Kelly skated to the center of the ice and snapped a shot into the top corner of the net for his career-best 20th goal.

Parenteau got the Islanders within 4-3, scoring his 18th of the season with 5:07 to go, but Bergeron restored Boston's two-goal lead 1:26 later, and Krejci made it 6-3 just 24 seconds after that.

NOTES: Bruins defenseman Dennis Seidenbeg made the trip to New York but sat out because of an infection in a cut above his left knee. Fellow defenseman Adam McQuaid (injured eye) didn't travel with the team after being sent face first into the boards on Thursday by Washington's Jason Chimera. He had a cut and swelling around his eye, but the Bruins said he didn't sustain a concussion. Mike Mottau was in the lineup for the first time in 11 games since March 10. ... The Islanders recalled Haley from Bridgeport of the AHL to fill in for Casey Cizikas, who was sidelined by an undisclosed upper body injury. ... Bruins defenseman Johnny Boychuk played in his 200th NHL game.