Tempe, Ariz. • Utes sophomore center Jayce Johnson’s potential has been evident since his days as a high school all-American and one of the top-rated college prospects in the country.

The 7-foot, 235-pound California native has shown flashes that he had grown closer to putting it together. However, those signs usually came with just enough near misses to keep questioning how much of an impact Johnson could actually make.

Johnson transformed into a difference maker in the paint on both ends of the floor in Utah’s overtime upset of No. 21 Arizona State in Tempe. He’ll need to produce a similar-caliber encore performance to help Utah (13-7, 5-4) get another upset win at 3:30 p.m. Saturday, this time against No. 11 Arizona (17-4, 7-1) and projected NBA lottery pick forward Deandre Ayton in the McKale Center in Tucson.

“He’s one of the hardest-working guys I know,” Utes junior guard Sedrick Barefield said about Johnson. “ He’s always in the gym. He’s always trying to improve. He always has a good attitude. He was my roommate for two years, so I’m going to vouch for him as much as possible.

“But he came in, he was rebounding, scoring. He was being aggressive. He wasn’t forcing the issue at all. He had a heck of a game for us. We know what he’s capable of in the future and right now. We believe in him a lot.”

Johnson notched a career-high 15 points grabbed six rebounds and matched a career high with three blocked shots in 28 minutes Thursday night when senior forward David Collette only played 13 minutes and scored just four points (two points in regulation). Perhaps more impressively, the sophomore with the knack for picking up fouls drew just one whistle.

“Off the charts ... a tremendous post presence for us not only scoring, [but] shooting free throws, defensively,” Utes coach Larry Krystkowiak said about Johnson’s play against the Sun Devils. “He did a great job on what we call the jump walls — when there is penetration to the rim and instead of fouling guys, getting verticals and making players take tough shots over you. It was an absolute clinic, and he stepped up big time. It was great.”

Johnson, who has come off the bench in all but one game, has averaged 6.8 points per game and the second-highest rebounding average (6.2 per game) on the team behind Tyler Rawson. Johnson also ranks second to Rawson in blocked shots (24 to 16), though Rawson has played more games and averaged 12 minutes more per game than Johnson.

Johnson played a big part in the Utes getting into an offensive rhythm in the first half against the Sun Devils on Thursday night. He led the team with 13 points in 13 minutes on 5-of-6 shooting in the first half. Johnson scored five consecutive points during a 12-0 run that gave the Utes a 27-21 lead, including when he completed a dunk while being fouled by Sun Devils forward Vitaliy Shibel.

Johnson has shot 52 percent from the field this season, and he’s shown a good feel for getting his shot off in traffic. However, he has made post moves then failed to finish around the rim or got his finger tips on potential put-back attempts only to have the carom away at times.

Johnson sank his jump hooks, layups and flip-ins around the rim Thursday night, and he completed that first-half dunk through contact, something he hadn’t done a lot this season.

“I’ve been getting in the gym working on my hook shot around the basket,” Johnson said. “... I’m thinking about going up to the basket and trying to dunk the ball or, if not, try to finish it at the rim. That’s kind of been my mentality change. I just wanted to go at the rim every time I go up. I think that’s kind of helped me finish the ball more.”

UTAH AT ARIZONA

Tipoff •
3:30 p.m. Saturday

TV • FOX

Radio • 700 AM

Records •
Utah 13-7, 5-4; Arizona 17-4, 7-1

Series history •
Arizona leads 32-29

About the Utes • Junior guard Sedrick Barefield has averaged 15.5 points per game off the bench in the past two games, including 17 points in Thursday’s overtime win at Arizona State. He has shot 56 percent from the field in those two games and gone 6 of 9 from behind the 3-point line. … Justin Bibbins ranks among conference leaders in scoring (eighth, 16.9 ppg), assists (third, 5.9 per game), free throw shooting (fifth, 89 percent) and 3-pointers made (3.7 per game) since the start of conference play. … The Utes have held their past three opponents to fewer than 80 points, including Arizona State in an overtime game.

About the Wildcats • The Wildcats rank first in the Pac-12 in field goal percentage (48 percent) and free-throw shooting (84 percent) through eight conference games. ... They’ve won 18 of 19 home games against Pac-12 opponents. … Allonzo Trier, a 6-foot-5 junior guard, leads the conference in scoring (19.9 ppg). He’s coming off a 23-point game in a win over Colorado on Thursday night. … Highly-touted 7-1, 250-pound freshman forward Deandre Ayton ranks third in the conference in scoring (19.7 ppg) and first in rebounding (10.9 per game). He has shot 62 percent from the field and blocked 1.8 shots per game.