One of the top words associated with Aaron Gordon’s much-heralded arrival at Arizona was “motor,” the nonstop intensity and passion he brings for the game.

It was never clearer why than Thursday, when Gordon appeared to be the most driven player on the floor while scoring a career-high 21 points in an otherwise ho-hum 69-43 Arizona win over Southern University at McKale Center.

Gordon scored most of his field goals, as usual, with dunks and layups but also mixed in his seventh three-pointer of the season and drew encouragement from the McKale Center crowd when he hit the free-throw line, making 4 of 10.

Overall, Arizona shot 45.8 percent from the field and outrebounded Southern 39-33.

The Wildcats were playing without center Kaleb Tarczewski, who sprained his ankle against Michigan last Saturday, but it hardly mattered. UA started starting forward Rondae Hollis-Jefferson at small forward, while moving Gordon to power forward and Brandon Ashley to center.

 While Gordon had 21 points and four rebounds, Ashley added 11 points and 10 rebounds. It was the fourth double-double of Ashley’s career.

The win moved top-ranked Arizona to 12-0 heading into their nonconference season finale on Monday against NAU. The Wildcats will then break for Christmas and return on Dec. 27 to begin preparing for the Pac-12 season.

Southern, a one-time invitee from the Southwestern Athletic Conference, dropped to 3-8.

Leading 34-19 at halftime, the Wildcats led only 36-26 when fans at McKale Center began cheering and jeering for more. Gordon broke them out of the funk with a three-pointer, just his seventh of the season, and added 3 of 4 free throws over the next five minutes while UA built its lead to 49-30 with 11:40 left.

The fans appeared acutely aware of Gordon’s free-throw issues – he entered the game hitting only 44.7 percent from the line -- cheering strongly when his first of the four free throws bounced off the rim and in, and then cheering wildly when he swished the second.

When Gordon returned for the final two free throws of that stretch, the crowd groaned when he missed the second.

The highlight of the first half, beside the dunk show put on by Gordon en route to his 10 points, came when an Air Force Master Sergeant surprisingly appeared to reunite with his family on the court after videotaping an address saying he was sorry he would miss Christmas.

While Gordon finished with 10 points and two rebounds in the first half, Ashley had eight points and six rebounds. The Wildcats shot 54.2 percent from the field but made only 6 of 16 free throws in the half.

Arizona took an early lead of 15-5 when UA coach Sean Miller began substituting beyond his usual top seven. He first put in reserve forward Matt Korcheck, and then used reserve guards Jordin Mayes and Elliott Pitts on the wings.

Meanwhile, Gordon almost singlehandedly kept the Wildcats comfortably ahead by putting on a show around the basket. He scored 10 points in the first 13 minutes of the half, with eight of them coming off layups or dunks.

Before the game, UA trainer Justin Kokoskie said Tarczewski did eight hours of rehabilitation on Wednesday but wasn’t healed enough to risk him playing tonight. Kokoskie said Tarczewski has been working on his strength, balance and conditioning.

“We’ll shoot for tomorrow or the next day but we’re also not going to put him in a position of risk,” Kokoskie said.

Tarczewski is planning to remain in Tucson during UA’s three-day Christmas break, and he’s expected to rehab the entire time.