Before the season, UCLA had the young, hot-shot quarterback that had the college football world -- and NFL scouts -- buzzing.

Now, USC does.

Redshirt freshman Sam Darnold is at the forefront of a Trojans resurgence that reached a peak with Saturday's 26-13 victory at previously undefeated Washington, which was No. 4 in the country. Darnold completed 22 of 33 passes for 287 yards -- the most allowed by the Huskies this season -- and two touchdowns.

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Darnold gets a different kind of stage this Saturday night.

USC (7-3, 6-2 Pac-12) has its first six-game winning streak since 2008 as it heads into a game against struggling crosstown rival UCLA (4-6, 2-5) at the Rose Bowl in Pasadena, Calif. The 10:30 p.m. ET kickoff makes it just the 11th night game in the history of the series.

The Bruins are without sophomore quarterback Josh Rosen, the former No. 1 quarterback recruit who has missed four games because of a shoulder injury and won't return this season. Darnold has replaced him as the L.A. star.

USC coach Clay Helton inserted Darnold as the starter, replacing Max Browne, for the fourth game of the season. The Trojans lost that day, 31-27 at Utah when the defense allowed a touchdown in the final minute, but it has been all victories since then, riding the spark that Darnold provided.

He is the reigning Pac-12 Offensive Player of the Week for his performance against the Huskies, who have one of the top defensive backfields in the country. Darnold is eighth nationally in passer rating with a rating of 165.8.

"He has just unbelievable game maturity," Helton said.

The Bruins, who are still pushing for a bowl, did end a four-game skid by beating visiting Oregon State last weekend 38-24.

"It's good to get a win," said Bruins coach Jim Mora. "They have been hard to come by this year. These guys have stayed together and have kept a great attitude. So, they got rewarded for it. That was great."

Mora said he has given away only two game balls in his nearly five seasons at UCLA. The second went to quarterback Mike Fafaul on Saturday.

Fafaul, starting his fourth game in place of Rosen, completed 25 of 47 passes for 281 yards. Mora praised the fifth-year senior for sticking it out and not transferring as a graduate student.

"He played behind Brett (Hundley), and then Josh got the job, and he has hung in there," Mora said. "He's everything that you want in a quarterback in terms of studying the game and it being serious to him. It's just great."

Fafaul's challenge this week against USC will be much more difficult than it was against Oregon State. The Trojans held Washington quarterback Jake Browning to 17-of-36 passing with a pair of interceptions by cornerback Adoree' Jackson.

Fafaul has thrown 10 interceptions in 198 attempts, and if the Trojans could fluster Browning, what will they do to Fafaul?

Darnold has had the advantage of a supporting run game -- Ronald Jones II has 487 yards on the ground in the past three games -- an All-American talent at wide receiver in junior JuJu Smith-Schuster and a veteran offensive line that has begun to play to its potential.

Fafaul has had none of that. UCLA's young line has struggled, there is no game-breaker on the outside and the Bruins are second-to-last nationally in rushing at 87.2 yards per game. UCLA gave carries to five scholarship running backs last week and will try to find hot feet this week from among Bolu Olorunfunmi, Soso Jamabo, Jalen Starks, Nate Starks and Brandon Stephens.

It won't be easy. USC held Washington to 17 rushing yards.

"Big men win the game," Helton said. "On both sides of the ball, our big men are really excelling these last six weeks."

UCLA's hopes rest with a solid defense that has allowed only one opponent (Utah) to score more than 27 points in regulation. Defensive end Takkarist McKinley leads the nation with 2.0 tackles per loss per game.

The rivalry game wraps up the conference season for USC, which finishes at home against Notre Dame. The Trojans are a half-game behind Colorado and hold a head-to-head tiebreaker. The Buffaloes, 6-1 in the league, finish with two games against ranked teams -- Washington State and Utah.

USC needs to win Saturday and have Colorado lose to have a chance to win the Pac-12 South. Utah, which is 5-2 in the Pac-12 with games left against Oregon and Colorado, holds the tiebreaker over USC.

The Trojans have won 13 of the past 17 games against UCLA, although two of the victories were vacated due to NCAA sanctions. USC won 40-21 last season.