When Steve Mills was hired in 2013 to be Knicks president and replace Glen Grunwald coming off a 54-win campaign, one of the Garden’s reasonings was Mills’ solid relationship with the powerful Creative Artists Agency.

That’s how much Knicks owner James Dolan cared about CAA. In an ironic twist, Mills ultimately was fired and will be replaced by one of their agent juggernauts, Leon Rose — who repped Carmelo Anthony, among others.

“MSG and CAA have been in bed for years,’’ one NBA executive told The Post. “This shouldn’t be surprising.’’

Rose, the former agent for LeBron James, was granted special privileges during the Melo/J.R. Smith era. The Cherry Hill, N.J., native was the lone agent allowed in the locker room after games, seen waiting on his guys.

Rose has connections that can help the Knicks — the obvious one being his role as the agent for Karl-Anthony Towns, whom the club has eyed as a potential trade candidate down the road if he becomes even more disgruntled with the Timberwolves’ losing. Rose also reps Suns star Devin Booker.

As for coaching candidates, Rose has worked before with John Calipari, who is heavily linked to adviser/mover-and-shaker William Wesley, also expected to join the Knicks’ staff.

New Knicks president Leon Rose (center) has been the agent for (left to right) Chris Paul, LeBron James, Carmelo Anthony and Kart-Anthony Towns.
New Knicks president Leon Rose (center) has been the agent for (from left) Chris Paul, LeBron James, Carmelo Anthony and Karl-Anthony Towns.Post photo composite

Rose has also had professional dealings with former Bulls and Timberwolves head coach Tom Thibodeau, a former Knicks assistant. Rose reportedly is on good terms with Jeff Van Gundy, and that could open the door for the former Knicks coach who never even got an interview in 2018, when the club hired David Fizdale.

“Something had to be done, and it definitely has some sex appeal,’’ said one rival agent. “And I do wonder if this means Calipari comes with him.’’

Rose doesn’t represent any of the current Knicks, but he is the former agent of Frank Ntilikina. The 2017 lottery pick fired CAA last year to go with French rep Bouna Ndiaye.

“He’s a good guy, he helped me with a lot through the draft process,’’ Ntilikina said of Rose. “He knows basketball and knows what he’s doing.’’

Hard feelings?

“No, not at all,’’ Ntilikina said. “It’s part of the business. We still have a good relationship.’’

It’s an unorthodox move, but one that is trending. Former agents Bob Myers (Warriors) and Rob Pelinka (Lakers) have made the transition well.

Rose has come a long way since the 2000-01 season, when his only client was Knicks 12th man Rick Brunson.

Rose has always been known for being very media-friendly and now joins an organization that has been criticized for being less than transparent.

Mills and acting president Scott Perry haven’t talked to the media since Nov. 10, when they hijacked Fizdale’s postgame press conference to put the coach on alert.

One NBA source said one of Mills’ failures was his lack of leadership qualities. Rose oversaw the CAA basketball department, so he was in a leadership role in that sense.

In a statement, Dolan said the search was ongoing as he’s “determined to find the right leader for the Knicks.’’

Dolan thinks that guy is Rose. If there were hard feelings over the Anthony trade negotiations with Houston and Oklahoma City in 2017, there aren’t any longer.

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