John Calipari’s star of the Kentucky-Arkansas game? He might be ready for a bigger role.

Antonio Reeves and Reed Sheppard carried the day offensively, Tre Mitchell filled in the gaps yet again, but it was another Kentucky Wildcat who drew John Calipari’s praise Saturday night.

“What did Ugo do for us today?” the UK coach gushed. “Ugo was the difference in the game.”

Kentucky beat Arkansas 63-57, eking out a victory in Bud Walton Arena four days after its most lopsided loss of the season. With 17 seconds left, Calipari subbed out Ugonna Onyenso.

The 7-foot sophomore made his way to the UK bench, and his head coach intercepted him as soon as he stepped on the sideline. A big smile on his face, Calipari gave Onyenso a hug. “I’m so proud of you,” the coach said, beaming.

It’s been a tough road for the 19-year-old from Nigeria, but he’s starting to carve out a meaningful role as a college basketball player at Kentucky.

And Saturday was the latest example.

“I like what’s he’s been through,” Calipari explained. “The foot, having to wait his turn, fighting for what you want. I keep telling him, ‘The rest of your basketball life, nothing will be given to you. You either take it, or someone will take it from you.’”

Onyenso was seemingly set for a breakout season before suffering a foot injury in July that sidelined him for five months. He didn’t make his debut until Dec. 16 — playing nine minutes while battling an illness in an 87-83 victory over North Carolina — but he also missed out on months of developmental time that would have been crucial for a player still learning the game.

He’s now coming along a little more quickly than anticipated, all that time watching from the sidelines taken into account.

On Saturday night, Onyenso tallied six points — on 3-of-4 shooting — with four rebounds and three blocked shots in 25 minutes. His plus-14 rating was the best on Kentucky’s team, and most of that came during the second half, when it was clear that the sophomore had earned Calipari’s trust.

Following an ugly first half in which the Cats scored four points in the first 10 minutes and trailed 26-24 at halftime, Calipari shook things up coming out of the locker room. He played Onyenso in place of regular starter Aaron Bradshaw. The UK coach switched those two about a minute into the half — after Onyenso mishandled an entry pass, leading to his only turnover of the game — but as the going remained tough, Calipari stuck with him.

Onyenso was back in the game before the first TV timeout of the second half, and Calipari didn’t take him out again for more than 10 minutes. He played most of that stretch alongside what turned out to be Calipari’s go-to combo against the Razorbacks: D.J. Wagner, Sheppard, Reeves, Mitchell and Onyenso.

Before the game, Calipari changed around his starting lineup for the first time in six weeks, sliding the returning Adou Thiero in for the struggling Justin Edwards, who had started all 18 of UK’s games until that point. After Saturday’s win, Calipari suggested he might not be done tinkering.

“Now, you say, ‘Well what does that do?’” Calipari said of Onyenso’s showing. “He probably moves up. You know, he may start now, and Aaron may come off the bench with Z.”

Bradshaw, who started the past nine games for Kentucky, had zero points and three rebounds in 12 minutes Saturday, playing just 4:33 after halftime.

Zvonimir Ivisic, who dazzled in his debut last weekend against Georgia, had zero points and two rebounds in just three minutes Saturday, not even getting into the game in the second half.

Bradshaw has struggled with foul trouble — he picked up two in the first half again Saturday and was whistled for his third with 16:14 left in the game — and Calipari has said Ivisic needs to “catch up,” especially defensively, before he can play meaningful minutes on a consistent basis.

With Onyenso in the game, Calipari knows he has a defensive threat.

The UK coach said after the win over Arkansas that it was the best pick-and-roll defense the Cats had played all season. Calipari said the reason was Onyenso’s presence.

“He’s long and active and can move his feet,” he said.

Onyenso now has 23 blocks in 149 minutes on the court this season. Only Mitchell (with 24 blocks in 645 minutes) has more.

“I really take pride in defense,” Onyenso told Jack Givens on the postgame radio show. “The fact that people, when they’re driving, they’ve got to think about if they’re gonna make a layup or not — that gives me joy. Knowing that defensively, people are scared to come in. I did what I usually do, getting blocks. And I’m not surprised.”

His teammates were impressed.

“Ugo was huge tonight,” Sheppard said. “Blocking shots, getting rebounds. And that’s what we need Ugo to do. … He stepped up and played really, really good.”

“He was incredible,” added Reeves. “Ugo’s definitely gotten better.”

The fifth-year player said his younger teammate has especially improved with reading the game. He recalled one particular play where Onyenso faked a give and go to Reeves in the corner, then turned and flew down the baseline for the open dunk himself. That basket gave Kentucky a 40-39 lead midway through the second half. Forty seconds later, the Wildcats took the lead for good.

“Tough plays like that — that we need out there,” Reeves said. “And he’s coming up with blocked shots, rebounds. Coach said it himself, he’s playing very well right now. … He’s definitely doing what he’s doing out there.”

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