NBA

Knicks’ Lin signs new rep to direct free-agency fight

The Knicks’ Jeremy Lin, with free agency looming July 1, is beefing up for negotiations by retaining the powerful Washington-based agent Jim Tanner of Williams & Connolly.

The undrafted Harvard point guard was using little-known Roger Montgomery, who guided a small agency in San Antonio. A release said Montgomery will continue to work with Lin in conjunction with Williams & Connolly, a Beltway law firm that has former President Bill Clinton among its many political clients.

Tanner said he first met with Lin and his family when he came out of college, but didn’t sign him. They became reacquainted two months ago, after Lin’s left- knee surgery. Powerhouse agency CAA also tried to sign Lin, but failed.

“What’s most interesting in this process is how much interest he has off the court, with so many companies already expressing interest,’’ Tanner told The Post. “He had a phenomenal year in terms of his performance. He captured everyone’s imagination. Everyone can identify with his story being an underdog, overcoming odds and excelling.’’

Tanner declined to comment on Lin’s chances of re-signing with the Knicks, saying he is too new to the situation.

Lin is supposed to play for the U.S. Select Team that will face Team USA during scrimmages starting July 5, but his contract won’t be finalized until July 11. There is precedent for free agents pulling out of the Select Team.

“I don’t want to comment on that yet,’’ Tanner said.

Tanner also represents, NBA stars Grant Hill, Shane Battier, Tim Duncan and Ray Allen, the latter a free agent who may have interest in the Knicks if they still have their $5 million mid-level exception after a union hearing.

Montgomery and Tanner will collaborate on Lin’s new contract that could get tricky if another team (which has to be under the cap) offers him a back-loaded proposal. The Knicks can match any offer, but a team under the cap can go as high as $15 million in the third year of a deal. The first two years can’t be higher than the average salary (roughly $5 million). The Knicks may or may not have to use their mid-level exception on Lin, pending Lin’s Bird Rights hearing.

Knicks general manager Glen Grunwald, a well-decorated lawyer out of Northwestern, has said he will re-sign Lin, but Montgomery recently told The Post he didn’t consider that a slam-dunk.

Montgomery needed help mostly because Lin is a marketing gold mine. There has been criticism Lin hadn’t cashed in with enough endorsements.

The new firm will represent Lin in all areas of contractual agreements, marketing endorsements, licensing, personal appearances, media relations, community investments, and other business opportunities.

“I believe Jim and the team at Williams & Connolly are the best fit for me in all aspects of my career,” Lin said in a statement. “With the quality and character of their firm and clients, their extensive basketball experience and tremendous success in athlete representation, I am confident that Williams & Connolly will provide me with the guidance I need to continue to develop personally and professionally. I am excited to have them work with Roger Montgomery and my current team.’’