The only thing Knicks fans care about now with Wisconsin senior power forward Nigel Hayes is he’s “big and dirty” under the boards.

An NBA source confirmed Hayes has signed with the Knicks’ summer-league team after going undrafted. Hayes will get a partial guarantee for training camp. He’s a 6-foot-8 power forward with a 7-foot-3 wingspan, and scouts say he has a good mid-range game, post moves and is a tough rebounder.

But about those streets of New York. When Hayes, who has an engaging personality, was in New York in March for the East Regional of the NCAA Tournament, the product of Toledo, Ohio, created a stir at the Garden when he opined about the city’s cleanliness.

“I don’t really like New York,” Hayes said. “It’s too big. It’s dirty. There’s trash everywhere. There’s too many people. And it’s cold right now. It’s nice to look at in the movies and stuff, but I’ve had my share of it. I’m just trying to come here and win some basketball games.”

Asked if he would change his tune if he were drafted by the Knicks, Hayes barely softened.

“You’d have no choice,’’ said Hayes, who averaged 14 points and 6.6 rebounds as a senior. “It’s just something you’d have to live with it.”

His agent, Kevin Bradbury, told The Post on Friday the free-spirited Hayes was simply entertaining the media.

“He was completely joking,’’ Bradbury said. “He said afterward how much he loves the energy in this town, how playing at the Garden would be a dream. Not gonna lie, he is from Toledo, Ohio, so New York is real big. But he is a free thinker. He says what’s on his mind. The fans will love him for it.’’

Hayes will be joined by another rookie free-agent signee: Vanderbilt sweet-shooting 7-foot-1 center Luke Kornet, a late bloomer who didn’t get his first scholarship offer until May because he was just 6-foot-4 as a high school junior. His father, Frank, played for the Bucks — and Vandy.

According to a source, Kornet will have a two-way deal, a wrinkle of the new CBA as rosters can expand to 17 players. Kornet can be Knicks property and spend the season going back and forth to the newly named G-League. He’ll get paid minor league money for the days he’s with Westchester.

In an interview with The Post before his Knicks workout, Kornet said he impressed teams with his movement after a senior year in which he battled an early-season knee sprain.

Kornet is considered a “stretch 5’’ — and will battle with second-year man Marshall Plumlee, who has a partially guaranteed deal. Kornet earned the SEC’s All-Defense honors and averaged 13.2 points and 6.5 rebounds as he led Vanderbilt to the NCAA Tournament.

“The biggest thing is they’re seeing me move a lot better,’’ Kornet told The Post. “I was well under 100 percent early in the season.”

Florida guard Canyon Barry, Rick Barry’s son, also was signed to the Knicks summer league team.