Washington Capitals goalie Jaroslav Halak deflects a shot off his...

Washington Capitals goalie Jaroslav Halak deflects a shot off his mask during the second period against the Los Angeles Kings on Thursday, March 20, 2014, in Los Angeles. Credit: AP

The Islanders have found their No. 1 goaltender. Jaroslav Halak agreed to a four-year, $18 million contract Thursday, three weeks after the Isles acquired the 29-year-old's negotiating rights from the Capitals.

After years of instability in net, the Islanders seemingly have found a proven goaltender in the prime of his career.

"I think it's a perfect fit,'' Halak told Newsday from his home in Bratislava, Slovakia. "They have a good group of young guys who are only going to get better.''

Halak brings the sort of career numbers -- 144 wins, 2.38 goals-against average, .918 save percentage and that under-30 age -- that the Islanders haven't had in a goaltender for a long while.

General manager Garth Snow knew his team's league-worst .894 save percentage in 2013-14 was a big reason for the team's step back in the standings, so he decided to be aggressive even before a few big names would become available on July 1.

"We've still only got one goaltender under contract, but this is a good first step,'' Snow said. "Jaro's ability to stop the puck is obviously high-end. We think this is a good deal for both sides.''

Halak began the 2013-14 season as the top goaltender for a very good Blues team, but that organization decided it needed more and packaged Halak in a deal for Sabres star goaltender Ryan Miller. Buffalo flipped Halak to the Capitals five days later. So Halak was not quite as eager to test the free-agent waters after all that moving around.

"It was a crazy year,'' he said. "Now I know I'm in a good situation, they've got a good team and they've got a great building, the Barclays Center, to be their home next year. Right now, I'm very happy.''

Snow made another move Thursday, officially telling the Sabres that the Islanders will hold on to their 2014 first-round pick, No. 5 overall, and send their 2015 first-rounder to Buffalo to complete the Thomas Vanek deal.

Snow said his plan since the season went south was to retain this June's pick.

"We can get a quality prospect at No. 5, or we can trade it for a quality player. Either way, it's an asset,'' he said.

"And we also don't see ourselves being in this position again next year.''

The Halak deal seems to be a step toward not being back in the draft lottery. Snow said he has had "good conversations'' with Evgeni Nabokov's agent to bring the 38-year-old back as Halak's backup, which would give the Isles a veteran tandem. Anders Nilsson already has told the team that he will be going to the KHL and the Islanders might bring back Kevin Poulin only as depth goaltending insurance.

More Islanders