NEW YORK -- The New York Islanders completed their first season sweep of the St. Louis Blues since the mid-1980s on Friday. More efforts like the ones they've produced this week and perhaps the Islanders can entertain the notion of returning to the Stanley Cup Finals for the first time in three-plus decades.

Center Frans Nielsen and right winger Kyle Okposo scored in the shootout and goaltender Thomas Greiss stopped both shots he faced in the bonus format as the Islanders edged the Blues 2-1 at the Barclays Center.

The Islanders' second straight 2-1 shootout victory -- they also beat the crosstown New York Rangers on Wednesday -- completed a perfect three-game homestand, extended their winning streak to four games and capped a sweep of the Blues, whom they beat 3-2 in overtime in St. Louis on Oct. 24.

The Rangers are tied with the Washington Capitals atop the Metropolitan Division, three points ahead of the Islanders, while the Blues' 34 points are second-most in the Western Conference.

"As long as you keep getting points on the board, it's good,'' Nielsen said. "You can't take too any chances there when the game is tied in the third period. You've just got to keep getting those points and then -- almost want to say you win the lottery in the shootout."

The Islanders might have won the lottery the last two games, but coach Jack Capuano didn't see anything fluky after New York -- which entered Friday eighth in the NHL in goals -- won back-to-back games in which it scored two goals or fewer for the first time in more than a year. The Islanders beat the Los Angeles Kings 2-1 on Nov. 6, 2014 before edging the Arizona Coyotes 1-0 two nights later.

"You've got to learn to win tight games -- not every night's going to be 4-3 or 5-4, you've got to win in different ways and I think our guys played well tonight defensively," Capuano said.

The Islanders (15-8-4) are 3-6-4 this season when scoring two goals or fewer and 16-46-14 in such regular season games since the start of the 2013-14 season. New York lost a seven-game Eastern Conference quarterfinal series to the Washington Capitals last spring, during which it went 1-3 when scoring two goals or fewer.

"This is what you want to do -- win games 2-1," Nielsen said. "That's what good teams do. You've got to learn to do that. When you don't play to your best, you've got to learn how to win those games, just keep it tight. That's something we started to work on last year."

The Islanders and Blues got plenty of experience in a tight game Friday. St. Louis took a 1-0 lead with 26.8 seconds left in the first, when defenseman Kevin Shattenkirk's shot from the left faceoff circle banged off the left post and past Greiss.

The Islanders had a handful of scoring chances in the second before finally tying the game on a nifty goal by center Mikhail Grabovski 6:39 into the third. A pass from center Ryan Strome hit Grabovski in stride as he closed in on goalie Brian Elliott, who deflected the shot. But Grabovski stayed with the puck and managed to backhand it into the upper right corner as he sailed past the net.

"Those guys work in practice, they work on it all the time, stopping at the net, doing little things," Capuano said. "'Grabo' followed the puck and fortunately for us we got the rebound."

The final minute of overtime featured three legitimate scoring chances. Blues center David Backes was stopped by Greiss on a breakaway with 42 seconds left. A slap shot by left winger Alexander Steen ticked off Backes' stick or skate about 20 seconds later.

"Not very many scoring chances either way," Steen said. "Unfortunately, we had some in the OT and couldn't convert them."

In the shootout, Greiss (31 saves) preserved the lead provided by Nielsen and Okposo by turning back shots from Shattenkirk and right winger Vladimir Tarasenko to close out the Islanders' first sweep of the Blues since 1984-85, the season after New York's fifth and most recent trip to the Stanley Cup Finals.

"I'm very impressed with their team -- they've got a helluva hockey club," Blues coach Ken Hitchcock said of the Islanders. "They've got a handful for teams out West. I mean, we played some good hockey and still couldn't beat them right now."

Elliott had 24 saves for the Blues (15-7-4), who have lost two in a row (0-1-1) and seven of 11 (4-4-3).

NOTES: The Islanders scratched RW Steve Bernier and D Brian Strait. ... Islanders Gs Thomas Greiss and Jaroslav Halak have split the last 12 starts, though Greiss has started three of the last four games. Halak is expected to start Saturday night when the Islanders begin a three-game road trip against the Ottawa Senators. ... The Blues scratched D Joel Edmundson, LW Magnus Paajarvi and RW Scottie Upshall. ... G Brian Elliott started for the Blues for the first time since Nov. 17 -- a span of six games. Jake Allen, the Blues' usual starter, will likely play Saturday night when St. Louis begins a five-game homestand against the Toronto Maple Leafs.