NBA

Knicks hang on to beat Grizzlies for sixth straight win

Guess who has the longest winning streak in the NBA? Yes, it’s the Knicks.

On the night Miami’s 27-game winning streak crashed in Chicago, the Knicks’ winning streak rolled to six straight. J.R. Smith went on another rampage, scoring 35 points as the Knicks knocked off Memphis, 108-101, Wednesday night at the Garden.

The Knicks built a 30-point lead late in the first half as Smith was setting the arena on fire, but the Knicks needed a 3-point bucket from Jason Kidd with 1:20 left to extend their streak.

So it wasn’t perfect, but the Knicks’ record is perfect since arriving in Utah on a four-game losing streak at the tail end of their West Coast trip.

Oh, how it has turned around. When the Knicks hit South Beach on Tuesday, the only team potentially carrying in a sizable win streak will be in blue and orange. They are 44-26 — a season-high 18 games over .500 — and victors over a club playing better than .600 ball for the first time since they beat San Antonio on Jan. 3.

“[The Heat’s streak] was going to go down sometime,’’ resurgent Kenyon Martin said. “We’ll take it and keep this thing going around here.’’

“We’ll take it,’’ Smith said. “They had a helluva streak. But we have to keep focus on our team and start our own. I don’t know about (27).’’

The Knicks are unbeaten since Martin became the starting center after Tyson Chandler went down with a neck injury and Pablo Prigioni was inserted in a two-point-guard starting alignment. Their defense has returned to November form, the offense is moving the ball, Smith has a new, well-rounded game and Carmelo Anthony has a new knee.

“There’s been a sense of urgency with our ballclub,’’ coach Mike Woodson said. “There are a lot of things at stake and we’re coming down to the stretch run and every game is important.’’

Smith scored 23 first-half points and wound up with 35 points for his second straight 30-plus outing. He was 10-of-18 from the field and made 12-of-13 free throws — again displaying his new modus operandi of attacking the rack relentlessly.

“He’s dialed in right now,’’ Anthony said. “He’s putting the team over the top.

“I don’t know what he’s having for breakfast. but hopefully he’ll keep it going,’’ Martin said.

Memphis came storming back to within five points with 1:39 left when Quincy Pondexter scored on a putback. But Kidd gave the Knicks a cushion , nailing a right-wing 3-pointer as Jarryd Bayless ran into him. Kidd missed the free throw that would have given him a four-point play, but the Knicks had an eight-point bulge and the Garden could breathe easier. Memphis got it down to four points, 103-99, with 33 seconds left but the Knicks hung on.

“It happens,’’ Woodson said of the blown lead. “For a back-to-back game, I was pleased with how we played.’’

Anthony finished with 22 and Iman Shumpert had an electric start and finished with 16 for only his fourth double-digit outing this season. Shumpert will be a key if the Knicks are to dethrone Miami and he’s starting to surge into form after offseason ACL surgery as the playoffs near.

“Shumpert started again in a great rhythm,’’ Anthony said. “Anyone knows an injury like that takes time.’’

“We are rolling,’’ Shumpert said. “We kept confidence in our locker room. We stuck with one another and we knew we’d get that feeling back.’’

Memphis guards Mike Conley (26 points) and Jerryd Bayless (24) combined for 50 points. Nevertheless, the Knicks, with Anthony helping on post defense, held Zach Randolph to just three shots and three points.

The Knicks’ fourth-quarter frustration got to Anthony as he picked up his 12th technical foul of the season after being upset he didn’t get a foul call on a low-post miss. But it didn’t overshadow the good — Shumpert racing to 13 points in the first quarter and getting off to a 6-of-6 start and Smith’s bang-up performance, continuing to pound opponents by driving.

“Our communication has been high on the defensive end,’’ Smith said. “We are playing smallball but able to rebound on a consistent basis.’’

It’s been quite a change in 10 days.

“Sometimes you can take a couple of beatings and it can wake you up,’’ Kidd said. “It is about understanding the part of the season you are at right now.”

marc.berman@nypost.com