NBA

GM: Knicks knew J.R. ‘likely’ needed surgery

LAS VEGAS — Knicks general manager Glen Grunwald said despite the delay in J.R. Smith’s knee surgery, he still expects him to be on the court with Metta World Peace when the team opens its season in late October.

Grunwald attempted to clear up the mystery yesterday on why the Knicks delayed Smith’s surgery to mid-July, creating the possibility he’ll miss all of preseason and perhaps the season’s first two weeks.

Grunwald said at season’s end the club knew Smith “likely, probably’’ needed knee surgery, but they agreed to see if the knee could heal on its own without a procedure.

Grunwald said waiting until mid-July was Smith’s preference to see if rehab would solve the issue. One league source said a “chip’’ was found in his patellar tendon, and it is not torn. Smith also had torn meniscus cartilage repaired Monday during surgery at New York’s Hospital for Special Surgery.

“J.R. had this problem all of last season, even before training camp,’’ Grunwald said on a conference call announcing the World Peace addition. “He was struggling with it. To his credit, he battled through it the whole year and was real warrior for us. At the end of the season, we knew it was probably, likely he’d have surgery.

“We wanted to see how it would react with a little bit of rest. It turns out the best thing for him and us was to get the surgery now and hopefully he’ll be ready in time for the regular season rollng around.’’

Smith’s timetable is three to four months, which means he won’t be ready for the start of training camp. At worst, he would miss the first two weeks of the regular season.

But Smith was willing to risk all that, Grunwald said, to avoid the knife. He even debated playing through it again.

“We owed it to him to see if he can avoid that,’’ Grunwald said. “He wanted to give it a chance to heal to get better with treatment, and it didn’t.

“We discussed it at length with J.R. The decision is J.R.’s. He wanted to give it a chance without having to have surgery, and it’s perfectly understandable. It didn’t get better. He stepped up and had surgery.”

Earl Smith, J.R. Smith’s father, told The Post in yesterday’s editions the Knicks thought it was more convenient for their medical staff and training staff to start Smith’s rehab in July after summer league — even if it put the season-opener in jeopardy.

“He’s committed to doing all the rehab and getting back as soon as possible,’’ Grunwald said. “J.R. has always been good in that regard in terms of putting in the work.’’

Grunwald said he was not queasy about giving Smith a three-year, $24.7 million deal — with a player option after the second year — last week despite a seemingly chronic issue.

“We’re pretty comfortable this is something fixable and won’t present many problems in the forseeable future – the next four years,’’ Grunwald said.

As far as World Peace, Grunwald said he told the Queensbridge product he was “the missing piece to our team.’’ Grunwald said he got “rave reviews’’ from the Lakers, who amnestied him Friday.

“We had no true three-man other than Melo [Carmelo Anthony],’’ Grunwald said. “He gives us versatility and flexibility to play different ways — big or small. He’ll add a lot to our team. And his contributions in the locker room as a leader is expected to be very important to our team. He can easily start or come off the bench.’’

Grunwald also called World Peace “a New York legend.’’

* Grunwald was asked about the possibility of Anthony opting out after the season and departing. One potential destination is the Lakers.

“We obviously love Carmelo,’’ Grunwald said. “We think he’s great for New York and New York is great for him. We see a long-term successful partnership with him as we go forward.’’ … Grunwald said the club “is in discussions’’ to re-sign Kenyon Martin, but also is looking at a center (Samuel Dalembert?) and a third point guard. The Knicks only have the vet minimum to offer. … A source said point guard Nate Robinson wasn’t on the Knicks’ list going into free agency but now could be a fallback if he accepts the vets’ minimum, which is highly unlikely. Grunwald said Robinson had “a great year in Chicago.’’