Mark Streit celebrates his third-period goal against the Pittsburgh Penguins...

Mark Streit celebrates his third-period goal against the Pittsburgh Penguins during Game 4 of the Eastern Conference quarterfinals. (May 7, 2013) Credit: Jim McIsaac

Mark Streit is still a month away from unrestricted free agency, but two sources already have told Newsday that the Islanders' captain will not return to the team next season.

Streit, 35, had spoken of wanting to return as the 2013 season wound down, but he and the Islanders are far apart in contract requirements with the July 5 start of free agency looming. According to a source, the Islanders offered Streit a three-year deal worth about $5 million a season, but Streit is looking for north of $5.5 million per season.

With the free-agent market for defensemen very thin, Streit could command $6 million per year and even possibly get a four-year deal. The Islanders wanted Streit back to keep the continuity Garth Snow has built, but the Isles general manager is also not interested in busting his salary structure to keep Streit.

Streit was named captain before the 2011-12 season and has been a reliable scorer from his defense spot since signing a five-year, $20.5-million deal in July 2008. He missed all of 2010-11 with a shoulder injury but returned and led Islanders defensemen with 47 points in 2011-12 and 27 in the lockout-shortened 2012-13 season. He also had five points in the six playoff games.

Streit is close with John Tavares -- the two share an agent, Pat Brisson of CAA, and Tavares traveled to Streit's hometown of Bern, Switzerland, to play in the Swiss League during the lockout. Now, it appears that Streit will pass the captaincy to Tavares this coming season.

Brad Boyes, another CAA client, is unlikely to return, according to the same sources. Boyes produced on a one-year, $1-million contract, scoring 10 goals and 35 points playing primarily on Tavares' right wing, and is looking for a longer-term deal. Talks are ongoing, but it appears Boyes will reach the open market.

The last of the Isles' potential unrestricted free agents, goaltender Evgeni Nabokov, is likely to sign before July 5. Both the Islanders and Nabokov are willing to agree on a one-year deal, according to sources, and the money is not believed to be an issue.

Notes & quotes: The Islanders will host their annual draft party at Nassau Coliseum on June 30. Doors open at 1:30 p.m. Free tickets are available to reserve through Current Isles Matt Martin, Matt Carkner and Eric Boulton will attend.

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