The fact that the Knicks are sitting three games above .500 as we head towards Christmas is surprising.

The fact that they’re doing it with Jeff Hornacek as the head coach should not be.

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No sane betting man – not even the most daring Bitcoin investor – might have thought Hornacek would not be in the lead chair this season.

He was hired, then handcuffed by former team president Phil Jackson, who was married to the triangle and mindfulness and meddling. Tough way for Hornacek to coach.

Jackson and the Knicks parted ways last summer. A new management team, headed by Steve Mills and Scott Perry then took over. New management almost always equates to a new coach.

And after the Knicks got off to a 0-3 start while looking dazed and confused after trading away Carmelo Anthony and adding Tim Hardaway Jr., Enes Kanter, Doug McDermott, Jarrett Jack, Michael Beasley and Frank Ntilikina, Hornacek’s future in New York seemed shorter than the amount of time it takes for virgin white snow to look like hardened black lava.

But to the credit of Mills and Perry, they showed one of the most important qualities those in power often lack – patience.

They knew the Knicks already were a blender full of question marks. Making a coaching change likely would have dislodged the lid, spewing the contents of that blender all over the Garden.

And they knew that Hornacek had turned a Phoenix Suns team that finished 25-57 in 2012-13, into a team that went 48-34 in his first season as a head coach. They knew he had two great mentors in Cotton Fitzsimmons and the tough Jerry Sloane.

So they let Hornacek coach. Since that 0-3 start, the Knicks have gone 17-11. At 17-14, they’re in the hunt for a playoff spot. Such talk over the summer would have gotten you a one-way ride to an insane asylum.

So why has Hornacek not merely survived, but gotten the Knicks to thrive?

Because he’s never tried to be anyone other than Jeffrey John Hornacek, a stand-up guy from a small city in Northeast Illinois.

Yep, he’s got Land of Lincoln in his veins – humble, hard-working, and most of all, authentic.

NBA players are not fools. The Knicks knew Hornacek had to march to a drummer not of his choosing last season. It might have diminished a lesser man, diminished a coach in his player’s eyes.

But combined with his authenticity, is a toughness that belies Hornacek’s sinewy frame and easy-going demeanor.

He suffered a torn meniscus in his left knee as a player at Iowa State. The damage got so bad Hornacek was told he might have a five-year NBA career, tops.

He played 14 seasons, limping as if one leg was shorter than the other when he was off the court. By his last seasons, he had absolutely no meniscus in that knee – it was bone grinding on the bone – and his range of motion was severely limited.

Hornacek, through sheer will, played through it.

“I don’t know how to explain it,” Hornacek told the Deseret News in 2000. “You have an injury, you play through it. And get used to it.

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Back then, you played hurt. You played injured. When the going got tough….

That’s the man currently coaching the Knicks. There is no one looking over his shoulder, no one ringing a triangle.

This is Jeff Hornacek’s team.

“He just has more freedom,’’ Kristaps Porzingis told reporters recently. “He’s running the stuff he wants to run. He’s more comfortable and balanced. You also feel that confidence from [the coaching staff] in what they’re doing. Players always feel that. There’s a difference between last year, definitely.”

That difference was refreshingly on display Thursday night when the Knicks simply outplayed the Eastern Conference-leading Boston Celtics, 102-93, in a raucous Garden. KP, returning from a knee injury, was 0-for-11 from the field. He sat the fourth quarter. Most of the starters sat the fourth quarter.

Hornacek played the players that were more effective. Beasley scored a season-high 32. He led a Knicks bench that outscored its counterpart 56-20. 56-20!

“We showed the character of this team,’’ said Beasley, “showed we got fight.’’

They showed what a Hornacek-coached team is all about.

The Knicks were 16-13 on Dec. 22, 2016, but the season was about to unravel. They would lose six straight and 9-of-10. Tension increased throughout the franchise. By the end of the season, it seemed a complete housecleaning was in order. The Knicks found order in Hornacek.

“I think Jeff is doing a very solid job for this team, getting an opportunity to add to the culture,’’ Perry recently told reporters. “He and I communicate on a daily basis. We have a strong relationship.

“I’m looking forward for him to continue to push these guys in the manner we want them pushed, continue to grow as a defensive team, grow our competitive edge.”

That was Hornacek’s trademark as a player – he competed with an edge.

The Knicks are starting to mirror that. Yes, there was the clunker in Charlotte the other night. And the Knicks need to become a better road team.

But there is depth and grit, while The Garden is electric for Knicks games.

“It’s a positive vibe at The Garden,” Porzingis told reporters. “We’re having fun, playing hard. It’s different without [Anthony]. He was here a long time. My first two years we didn’t make the playoffs. We were supposed to make the playoffs. It’s different.

“We as a young team, expectations are not as high. If we keep playing at this level, the playoffs are realistic for us.”

It is and Hornacek deserves most of the credit.

He has every player playing hard, one of the greatest compliments for a coach. His ego is as subdued as his conservative suits. His competitiveness is not overbearing but it is unrelenting.

He never lost these players, which is huge in a player’s league.

“It’s a little bit different group, different stuff we’re doing, more typical of what NBA guys play now; that’s what they’re used to and grew up playing,’’ Hornacek said. “They’re more comfortable. I think the chemistry is great.”

The chemistry is great. And it’s been fostered by the coach.

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