LOS ANGELES _ After a magical turnaround for UCLA and a methodical month on the bubble for USC, the Pac-12 and presumably a place in the NCAA tournament hung in the balance as the Trojans' Jonah Mathews fired a three-pointer with less than a second left in regulation.
UCLA had won its previous seven games, with a chance Saturday to secure at least a share of the Pac-12 title. USC had won just enough to keep its place on the bubble secure.
The senior guard's final shot fell, knocking UCLA off its perch atop the Pac-12 and giving USC a stunning, 54-52 victory at Galen Center in the regular-season finale for both teams.
The victory should cement a place in the NCAA tournament field for USC (22-9 overall, 11-7 in the Pac-12), no matter what happens in next week's conference tournament in Las Vegas. The postseason future for UCLA (19-12, 12-6) is less certain, after its late run was halted.
USC and UCLA earned first-round byes in the Pac-12 tournament for finishing in the top four in the conference.
It was Mathews who stopped the Bruins, coming alive again in the second half. The senior had just four points before halftime, but finished with a team-high 19. He also became USC's all-time leader in three-point baskets.
Still, the Bruins stuck around until the end, as they'd been known to do over the course of their winning streak. The Bruins trailed in five of those games, eventually clawing their way back.
Defense led the way over that run, as UCLA hadn't lost a game all season in which it held a team to under 73 points. Until Saturday.
But even as Cody Riley knocked down two free throws to take a lead with nine seconds left, there was no comeback in the cards.
Riley finished as UCLA's leading scorer with 13 points, while Chris Smith added 12 to go with six rebounds.
None of the Bruins seemed to find their rhythm on offense. They finished shooting a miserable 31%, while USC caught fire after halftime, shooting 58%.
Neither team could find much of an offensive rhythm at the start. UCLA shot 29% in the first half, while USC was only marginally better at 31%.
After holding Onyeka Okongwu to just four points in the first meeting, the Bruins slowed the Trojans' top freshman again early. For 11 minutes, the potential future lottery pick barely touched the ball.
But Okongwu came alive soon after that, scoring eight of 11 to finish the first half. In what's likely his final game at Galen Center, Okongwu finished with 16 points and six rebounds.
