LOS ANGELES — Oneyka Okongwu scored 22 points, and Elijah Weaver hit a clutch 3-pointer to force overtime as USC rallied from a 21-point second-half deficit to earn an 82-78 victory over Stanford on Saturday.

Weaver continued to deliver for the Trojans in overtime, scoring eight of his team’s 13 points. He finished with 13. His 3-pointer at the regulation buzzer was his only make from distance in five attempts.

USC trailed 69-64 with 33 seconds remaining in regulation after Stanford’s Lukas Kisunas made a layup. The Trojans took over from there.

Okongwu made a layup with 11 seconds remaining, and after a Daejon Davis turnover on the inbound pass, Weaver hit his off-balance 3-pointer while getting fouled by Davis on the play. Weaver missed his free throw that would have given the Trojans the lead.

Jonah Mathews scored 19 points and Ethan Anderson added 11 as the Trojans (15-3, 3-1 Pac-12 Conference) won for the ninth time in their past 10 games and improved to 2-0 at home in conference play and 8-1 in their own building this season.

Oscar da Silva scored 21 points, and Spencer Jones added 18 as Stanford (15-3, 4-1) lost its first conference game. Tyrell Terry had 16 for the Cardinal.

Stanford lost for just the second time in its past 10 games with the other defeat to No. 5 Kansas at home.

Okongwu added nine rebounds as the Trojans, who had a 38-31 advantage on the boards.

The Cardinal dominated the first half, closing it on a 7-0 run to take a 45-25 lead into the break. Stanford was and 6 of 10 from 3-point range in the opening 20 minutes.

The Trojans made their move early in the second half with a 15-2 run to cut the deficit to single digits at 48-40. But a 9-2 Stanford run, capped by a 3-pointer from Spencer Jones, put Stanford back up 57-42 midway through the second half.

Another USC run, this one a 12-1 advantage got the Trojans to within seven at 60-56 with 6:25 remaining. They were able to get within 62-60 on a layup by Ethan Anderson with 4:47 remaining and refused to go away with a pressure defense that forced 17 turnovers

BIG PICTURE

Stanford: In a tale of two halves in regulation, the Cardinal shot 65.5% from the field in the opening 20 minutes and just 34.8% after halftime. … The Cardinal was unable to pass last year’s team which finished the season with 15 victories.

USC: The Trojans stayed in the game by going 27 of 36 from the free-throw line, while Stanford went 8 of 14.

UP NEXT

Stanford plays at Cal on Jan. 26.

USC plays at Oregon on Thursday.