LOS ANGELES -- Southern California ended February with six losses in seven games, its postseason hopes quickly fading.
That was then, this is now.
Playing with a frantic sense of urgency, the Trojans forced UCLA into its worst shooting performance of the season Friday night and upset the Bruins (No. 14 ESPN/USA Today, No. 15 AP) 65-55 in the Pac-10 tournament semifinals.
Now the Trojans have won four in a row and advance to Saturday's league tourney title game for the first time in two years. They'll try to win it for the first time against No. 23 Arizona State (24-8) after three runner-up finishes.
"People buried us because we lost six of seven," USC coach Tim Floyd said. "We get to live to fight another day."
Freshman DeMar DeRozan had 21 points and 13 rebounds, Dwight Lewis added 14 points and Taj Gibson had 13 points and 11 rebounds for the Trojans (20-12). They split twice with the Sun Devils in the regular season.
"We just stuck together, nobody panicked," Gibson said. "We were guarding, denying screens, rebounding the ball. We just guarded."
Josh Shipp scored 19 points and Nikola Dragovic added 12 for the Bruins (25-8), who shot a season-low 27 percent (19-of-70) from the field and trailed the entire game. They swept the Trojans in the regular season, but were denied a second straight berth in the tourney title game as their five-game winning streak ended.
"We got good open looks," UCLA's Darren Collison said. "They played good defense and they had a lot of interior help."
The Bruins were seeking a couple more victories to try to improve their NCAA tournament seeding and be able to stay in the West, where they advanced out of the last three years to make the Final Four.
"This was really a missed opportunity," coach Ben Howland said. "This could have really helped us if we'd won today and tomorrow."
The sixth-seeded Trojans needed a big win to bolster their NCAA tournament hopes, and their defense delivered.
They shut down Collison, UCLA's leading scorer who was held to four points -- 10 under his average and had a season-high seven turnovers in his final Pac-10 tourney. He also had four points in a February win against the Trojans.
"Darren's back really affected him, especially on back-to-back nights," Howland said, referring to Collison's sore tailbone that he hurt last weekend.
But Collison downplayed his condition, saying, "I'm never going to make excuses."
The Bruins were forced into shooting from the perimeter, and they were off the mark repeatedly.
"We just couldn't hit shots," Collison said. "They came out with great intensity and focus and they played desperately. We didn't play to our level."
The Trojans opened the game on a 20-9 run, with Lewis hitting back-to-back 3-pointers and DeRozan dunking twice to the raucous cheers of USC's fans.
The Bruins struggled offensively, hitting 9-of-29 from the field in the half and getting just two free throws from Collison. Their 31 percent shooting was the worst in a half this season, and got worse over the final 20 minutes.
But the second-seeded Bruins kept scrambling and outscored USC 19-13, including 10 points by Shipp, to end the half trailing 33-28. On their final possession, Collison missed a 3-pointer, but a couple of freshmen bailed him out. Jrue Holiday grabbed the offensive rebound and Malcolm Lee's tipin beat the buzzer.
Shipp opened the second half with a 3-pointer that cut UCLA's deficit to 33-31. The Bruins never got that close again in a messy game in which the teams combined for 42 turnovers.
DeRozan hit a 3-pointer and Daniel Hackett made a free throw with 2:44 remaining for a 57-42 lead, USC's largest of the game.
The Bruins made one final rally over the final 2½ minutes, outscoring USC 13-8 to end the game, but it didn't matter. DeRozan hit 5-of-6 free throws in the last 1:33 to preserve the win.
"I kept my poise," he said. "I pretended it was just another day in the gym practicing my free throws."
The outcome was a reversal of last year's semifinal meeting between the crosstown rivals, when UCLA won 57-54 and went on to beat Stanford for the championship. The win also allowed USC to avenge its worst loss of the season, a 76-60 defeat on UCLA's home court Feb. 4.
The Trojans earned their 20th victory for the third consecutive season, a first-time feat at the school best known for its national championship-caliber football team under coach Pete Carroll, who was on hand. Former UNLV coach Jerry Tarkanian sat next to actor Denzel Washington, and dozens of NBA scouts were in attendance.