Giannis Antetokounmpo of the Milwaukee Bucks drives to the basket...

Giannis Antetokounmpo of the Milwaukee Bucks drives to the basket against Noah Vonleh of the Knicks during the Christmas Day game at Madison Square Garden. Credit: Errol Anderson

It was a day in which being envious of other people’s gifts is bad form. But forgive Knicks fans if they looked at the Madison Square Garden court on Tuesday and imagined what it must be like in Milwaukee.

Well, not actually in Milwaukee, but rather what it must be like being in the shoes of Bucks fans, who have what every NBA team needs to contend: a signature star.

That would be Giannis Antetokounmpo, also known as “The Greek Freak” because of his nationality and preternatural physical gifts, and more recently known as a leading early contender for NBA MVP.

After a sluggish start in his first Christmas appearance, he took over in the third quarter, during which the Bucks outscored the Knicks by 14 points. The visitors cruised to a 109-95 victory.

Antetokounmpo totaled 30 points, 14 rebounds, four steals and three assists in 35 minutes. In the third quarter alone, he had 11 points and shot 5-for-6, including a 2½-minute stretch in which he had a 17-foot jump shot, an assist, a driving layup, a steal and a dunk.

When he took a seat for good with 1:15 left, many in the sellout crowd cheered.

“It’s amazing,” he said. “It’s the Mecca of basketball. It’s why New York is so special. The energy, the atmosphere, is great. They don’t just cheer about their team, they cheer basketball. They’re happy that they feel that excitement.

“Not just for me, for everyone, it’s fun to play in New York.”

If that sounded like an early hint about future interest as a free agent — relax. Antetokounmpo is under contract through 2020-21.

For now, the Knicks are holding out hope that the even taller guy sitting in street clothes on their bench can be their answer to Antetokounmpo.

Alas, there is no sign that Kristaps Porzingis will return from an ACL tear anytime soon, so who knows?

Anyway, Porzingis, 23, who injured himself when he dunked over Antetokounmpo last February, is not close to him as a player at this stage.

Antetokounmpo said going against Porzingis was not on his mind Tuesday, but he added, “I definitely want him to come back healthy. He’s a big piece of the New York team.”

The last time Antetokounmpo played in New York, on Dec. 1, Knicks reserve Mario Hezonja dunked on him, then stared and stepped over him, prompting Antetokounmpo to suggest he might punch him in the groin next time.

In the locker room before the rematch, Enes Kanter jokingly suggested that Hezonja wear a protective cup just in case. The Knicks showed a replay of the incident on their video board before the game. But Hezonja never left the bench.

Noah Vonleh was the primary defender on Antetokounmpo and made him work for everything he got. He also managed a dramatic block on him. It was not enough.

“That’s a matchup nightmare for a lot of guys,” Vonleh said.

Said Knicks coach David Fizdale, “The guy is just a physical beast.”

Exactly. Again: The Knicks need someone like that.

Everyone who closely follows the NBA knows what Antetokounmpo can do. But perhaps some casual fans got a sense of him through the nationally televised game — the Bucks’ first on Christmas since 1977.

He also flashed some personality. When asked about missing his first dunk attempt, he said, “I was so excited that I went a little bit too high and I thought the rim was a foot taller. That’s why I missed it. I’m being honest with you.”

The ball bounced to teammate Malcolm Brogdon, who made a three-pointer. “Please tell the NBA to give me an assist,” Antetokounmpo joked.

Several times, he used the word “fun” to describe the whole experience.

“Hopefully we can now play many more years to come,” he said. “This is one of the highest stages. Special teams play on Christmas Day.”

More to the point: Special players do.

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