Plenty on the line for UCLA, USC

The color scheme for tonight's cross-town rivalry game at the Galen Center -- UCLA wearing its road blue, USC its home, er, black -- could go a long way toward describing how the loser might feel with a month left before the NCAA tournament.

A UCLA loss would give the sixth-ranked Bruins their first two-game losing streak of the season and further pierce their aura of invincibility in the Pacific 10 Conference. It would also endanger their hopes of gaining a top seeding in the NCAA tournament and becoming the UCLA Bruins of Anaheim come the first round.

A defeat would be even more troublesome for USC. It would move the Trojans back to .500 in conference play and put them squarely on the NCAA tournament bubble, making their margin for error smaller over the regular season's final weeks.

"It's a must win game for us," UCLA freshman center Kevin Love said. "Of course we don't want to lose to SC twice in a row and it is a big rivalry game, but for us in the Pac-10, we want to win this game coming off a loss."

Black and blue also served to accurately depict the way things were going in the trainer's room at each school this week, particularly at USC.

On Monday, tests revealed that sophomore guard Daniel Hackett had a stress fracture in his lower back and might sit out the rest of the season.

On Wednesday, star freshman O.J. Mayo pulled his left groin and was unable to practice the next day.

On Friday, freshman guard Marcus Simmons said he would try to play on a chronically sprained left ankle that was admittedly only about 75%.

The injuries left the Trojans with only two fully healthy scholarship guards -- sophomore Dwight Lewis and freshman Angelo Johnson -- going into a game against one of the deepest and most physical teams in the country.

"It would be great if we huddled 30 seconds between every play and we would have enough guys to get through a game, but we don't," USC Coach Tim Floyd said.

"It's up and down and if you have foul problems, you have a lot of things you have to work through."

Nevertheless, those who give the Trojans little chance to sweep the season series might be well served to remember that A) USC won last month at Pauley Pavilion, and B) the Trojans beat the Bruins two years ago under similar circumstances after losing star guard Gabe Pruitt to a knee injury.

"We're not desperate," Hackett said. "You've got guys that can play out there. It's too bad that I'm not able to help my teammates, but I'm 100% confident that they're going to come to play because that's what they do. They're competitors."

The absence of Hackett could force Floyd to try to get 15 to 20 minutes combined from Simmons and Ryan Wetherell, a seldom-used walk-on guard. It might also prompt Floyd to alternate between the Trojans' usual man-to-man defense and a zone that is less taxing.

UCLA Coach Ben Howland said his team would "spend all week" in practice working on attacking the triangle-and-two defense that USC unfurled during its 72-63 upset victory over the Bruins last month, but Floyd might have to abandon that scheme considering that Hackett was one of its central components.

The Bruins also expressed concerns about fixing the defense that allowed the Trojans to shoot 60.9% and amass 17 layups and dunks during the teams' first meeting.

"They kept getting dunks, getting layups," said Kevin Love, who was victimized by counterpart Davon Jefferson on one particular dunk that quickly found its way onto the Internet. "That was as poor a defensive output as we've had all season."

UCLA's defense wasn't exactly stout during its 71-61 loss to Washington on Sunday, but the Bruins have tended to play better immediately after defeats. They rattled off nine consecutive victories after a 63-61 loss to Texas in December. Then, after the USC defeat, UCLA blew out its next five opponents by an average of 18 points.

The Bruins' attempts to ward off a two-game losing streak and maintain their hold on their lead in the Pac-10 race may supersede any revenge factor against the Trojans.

"For us, this is bigger than the rivalry," junior guard Darren Collison said. "We're not even looking at that, not looking at the first game, not looking at the second game. We're in a battle right now for the Pac-10. We have no more room for losing.

The Bruins' quest for a third consecutive conference title got a boost Friday when forward Luc Richard Mbah a Moute participated in his first full-contact practice since spraining his left ankle early this month. Mbah a Moute is listed as probable for tonight's game.

In a possibly unprecedented move, USC is expected to wear black uniforms tonight as part of a "Black out the Bruins" promotion in which fans are also encouraged to wear black shirts.

If things go awry for the Trojans, a festive atmosphere could turn funereal.

TONIGHT

UCLA at USC, 7, FSN Prime Ticket

Site -- Galen Center.

Radio -- 570, 710.

Records -- UCLA 21-3 overall, 9-2 Pac-10; USC 15-8, 6-5.

Update -- Mayo said he practiced Saturday and should be "100%" for tonight's game. The Trojans are bidding for their first sweep in the series since 2003-04.

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