A future Hall of Famer might become available, so Billy King did his due diligence and made the call.

Multiple sources told the Daily News that the Nets GM inquired about Kevin Garnett’s desire to join Deron Williams in Brooklyn, but King didn't get an answer while uncertainty surrounds the Celtics.

Garnett, 37, has a no-trade clause in his contract, which he vowed not to waive last season. But circumstances changed dramatically with the Celtics following a first-round playoff loss to the Knicks, with GM Danny Ainge committing to rebuilding and Doc Rivers bolting to the Clippers.

A proposed deal that would’ve sent Garnett to the Clippers with Rivers was blocked by the NBA because it’s illegal to package a coach with players. Rivers’ new contract includes a stipulation that the Clippers and Celtics can’t swap players until the end of the 2013-14 season.

So Garnett and his two-year, $24.4 million contract are seemingly on the market. His teammate, Paul Pierce, is probably also on Brooklyn’s radar after being a target for consecutive trade deadlines.

As much as the Nets would love Garnett, it’s an unlikely pairing given the obstacles. Not only is it still unclear whether he’d agree to join the Nets -- which is what King was hoping to figure out by reaching out to a third party -- there’s also a very high hurdle of negotiating an inter-division trade.

But it’s no surprise King inquired about Garnett, a 15-time All-Star and former MVP. The Nets not only desire a reliable starting power forward, they could use a vocal and respected leader. Garnett fits the mold.

He was the Nets’ longshot free-agent target last summer, when King missed out on Dwight Howard before signing Kris Humphries to a two-year deal.