LEXINGTON, Ky. -- Kentucky's upside for its youthful roster after an awful first half was having another 20 minutes to make up for it.
The Wildcats actually took control in less than 5 minutes, surprisingly with a zone defense that especially paid off for Hamidou Diallo.
Diallo scored 13 second-half points, most of them during an 18-0 run, and No. 5 Kentucky shot 59 percent after halftime to rally past Utah Valley 73-63 on Friday night in the opener for both schools.
One of Kentucky coach John Calipari's youngest rosters since arriving in Lexington showed its inexperience by struggling on both ends and trailing 34-25 at halftime. The Wildcats emerged from the break more energetic to make the pivotal run over 3:22 with eight consecutive baskets, including back-to-back transition dunks by Diallo.
"We just had more confidence, more energy, and got all those first-half jitters out of the way," said the redshirt freshman guard, who finished with 18 points and five rebounds. "We just came out fired up and ready to play."
Shai Gilgeous-Alexander added 13 points, Kevin Knox 12 and Nick Richards 10 in the debuts for six of Kentucky's eight newcomers including Diallo.
More remarkable was Kentucky's use of the zone, which Calipari admittedly dislikes. Something had to be done with Utah Valley frequently beating the Wildcats inside, putting a crowd of 19,807 on edge and worried about a huge upset.
Kentucky's youngsters avoided that fate by executing the 2/3 zone well, creating turnovers leading to transition baskets and a few highlight dunks.
"We went zone and it kind of got us going," Calipari said. "That's what we should use the zone for. We had too many guys that were just getting beat on the dribble, too many guys out of position. That's what happens when you have all freshmen and a couple of sophomores."
Considering the benefits, Gilgeous-Alexander looks forward to seeing how the scheme works with more practice.
"It's definitely going to be a big help for us," he said. "We have a lot of length, and it's going to be tougher for the other team's offense to score on us."
As well as it worked for that stretch, Kentucky still had to work to put away the veteran Wolverines. But the Wildcats eventually built a 57-47 lead with 7:32 remaining and withstood several Utah Valley charges down the stretch to win the inaugural meeting between the schools.
Kenneth Ogbe had 12 points and Jake Toolson added 11 for the Wolverines, who committed 20 turnovers leading to 23 Kentucky points.
"We haven't spent a lot of time preparing (for the) zone yet," Utah Valley coach Mark Pope said. "It did what it was intended to do. It made us a little bit more passive and our guys don't have a feel for it, so what happened wasn't transition defense. It was turnovers in transition defense that really killed us."
Utah Valley: The Wolverines' advantage in experience showed throughout a first half in which they held Kentucky to 22 percent shooting and outrebounded the Wildcats 25-16. Just as quickly, they couldn't keep up with their younger counterparts after the break and shot just 41 percent overall. The outcome spoiled the homecoming for Wolverines coach and Kentucky alumnus Pope, a member of the Wildcats' 1996 NCAA championship team under Rick Pitino.
Kentucky: Freshman nerves showed as the Wildcats struggled shooting the ball -- missing 15 consecutive shots at one point -- and were frequently outhustled inside. Turning up the tempo quickly shifted momentum and their statistics, as they finished 41 percent from the field and nearly even on the boards (38-37). Sophomore forward Wenyen Gabriel had seven points and 13 rebounds.
Utah Valley's season-opening journey gets even tougher as it visits Tobacco Road on Saturday night to meet top-ranked Duke.
Kentucky hosts Vermont on Sunday, playing an NCAA Tournament team that won 29 games last season as a final tuneup before facing No. 4 Kansas in Chicago on Tuesday.
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