Oklahoma could find itself out of the national title race before the end of September.

The 21st-ranked Sooners (1-1) enter Saturday’s game against UCLA trying to jump-start a season that has gotten off to an unusually slow start.

Oklahoma hadn’t lost a September game under coach Bob Stoops before the Sooners were stunned in Norman, Okla., by TCU two weeks ago. They followed up that performance by struggling for three quarters with Tulsa before finally pulling away in the fourth.

Now the Sooners face a tough road game against UCLA (2-0), which has scored 107 points while rolling to two easy victories.

“We need to make something of this week,” Stoops said.

Since going 7-5 in 1999, Stoops’ first season at Oklahoma, the Sooners have lost only eight games and been in the national title hunt heading into late November every year.

With Big 12 Conference play still a couple of weeks away, the Sooners are in no danger of taking themselves out of contention for their fourth straight Bowl Championship Series game and fifth overall under Stoops.

But if they lose to UCLA on Saturday in the Rose Bowl, they’ll have no shot of getting back there in January for the BCS title game.

Across town, No. 1 Southern California resumes its quest for a third straight national title after a week off with a home game against Arkansas.

The Razorbacks last played the Trojans in 1974, the third of three straight years in which they met. Arkansas won that game, 22-7, after losing the previous two years to USC.

Back then, the Razorbacks were nationally ranked with championship aspirations of their own. The current Razorbacks are coming off a 28-24 home loss to Vanderbilt.

“There were so many plays you can pick out and you say, ‘If, could of, would of,’ and that shows you there’s a fine line between winning and losing,” Arkansas coach Houston Nutt said. “We have to correct and improve and go play this other team called USC.”

A victory over USC by Arkansas would rank among the biggest upsets in college football history.

Twenty-one other top 25 teams are in action Saturday, including three games matching ranked opponents, all involving teams from Florida.

No. 5 Tennessee is at No. 6 Florida for Urban Meyer’s first Southeastern Conference game as Gators coach. No. 17 Boston College plays its first Atlantic Coast Conference game at home against No. 8 Florida State. No. 13 Miami looks to avoid an 0-2 start in the ACC when it plays at Clemson.

No. 2 Texas, coming off a huge victory at Ohio State, plays Rice. The Owls have lost 37 of the last 38 to the Longhorns.

No. 4 Virginia Tech plays host to Ohio, which beat Pittsburgh in overtime last week.

No. 7 Georgia is home for Louisiana-Monroe; No. 9 Ohio State entertains San Diego State; and No. 10 Notre Dame tries to break a four-game losing streak in South Bend, Ind., to Michigan State.

Oregon State visits No. 11 Louisville; No. 12 Purdue is at Arizona; No. 14 Michigan plays host to Eastern Michigan; and No. 15 California plays Illinois at home.

Connecticut travels to No. 16 Georgia Tech; Northwestern plays at No. 18 Arizona State; and No. 19 Texas Tech entertains Sam Houston State, the first of two straight Division I-AA opponents for the Red Raiders.

No. 22 Iowa expects quarterback Drew Tate to be back in the lineup against Northern Iowa. Tate was knocked out of last week’s loss to Iowa State.

No. 23 Fresno State plays at Oregon, USC’s opponent on Sept. 24. No. 25 Virginia plays Syracuse at the Carrier Dome.