Texas was supposed to be a year away from challenging for No. 1.

There were just too many questions: Could Colt McCoy cut down his interceptions? Could the Longhorns find a running game? Could new coordinator Will Muschamp turn a struggling defense into a playmaking one?

And after five consecutive blowouts against a soft early schedule, could they trade punches with a heavyweight such as Oklahoma?

The answers keep coming up yes and the Longhorns (6-0, 2-0 Big 12) are a surprise No. 1 after knocking off the previously top-ranked Sooners, 45-35, Saturday at the Cotton Bowl in Dallas. Texas is ranked No. 1 in the regular season for the first time since 1984.

"Right now, this team would be known for heart and character and toughness," Longhorns coach Mack Brown said. "Everybody has questioned this team, including me. I didn't know how good we are."

Everything starts with McCoy, a junior who became a serious Heisman Trophy contender after his 277 yards passing with one touchdown against the Sooners. He is completing 79 percent of his passes with 17 touchdowns and just three interceptions. Last season, he threw 18 interceptions but had none Saturday in a nearly flawless performance against the Sooners.

"He's just making those plays, and he knows when something's not working why it's not working," Brown said. "Last year, we thought he got frustrated some and tried to move probably a little bit faster than he should at times because he was trying to make plays on his own."

Just as important, McCoy's 348 yards rushing and four touchdowns have kept teams off balance, giving Texas a flavor of a multitalented threat at quarterback the Longhorns had when Vince Young tormented opponents in the 2005 national championship season.

"McCoy's a double threat. He can pass and run," Sooners linebacker Travis Lewis said. "He has a lot of weapons around him. They outplayed us with those weapons."

Texas rode its resounding Red River Rivalry upset right to No. 1.

The Longhorns leapfrogged No. 2 Alabama yesterday and sit atop The Associated Press Top 25 in the regular season for the first time in 24 years after beating Oklahoma, 45-35.

Texas' jump to No. 1 is the largest since Miami went from No. 6 to No. 1 Aug. 29, 1988, after beating preseason top-ranked Florida State, 31-0, to start the season.

Texas received 39 first-place votes and 1,599 points from the media panel. Alabama received the other 36 first-place votes and 1,582 points.

The Longhorns are the fourth No. 1 team this season, following Georgia, Southern California and Oklahoma. So it's just more of the same following an unpredictable 2007 season that had four No. 1 teams and eight different teams ranked second.

For the second time this season, three of the top four teams in Division I-A lost on the same weekend. While the losses by the previously top-ranked Sooners, Missouri and LSU weren't stunning, they did a number on the rankings.

Unbeaten Penn State moved up three spots to No. 3. The Sooners dropped three spots to No. 4 after their first loss. Florida jumped six spots to No. 5 after pounding LSU, 51-21, Saturday night.

No. 6 Southern California is followed by Big 12 rivals Texas Tech and Oklahoma State, which upset Missouri, 28-23, and has its highest ranking since November 1985 when the Cowboys were seventh.

No. 9 BYU and Georgia round out the top 10.

Missouri dropped eight spots to No. 11. The Tigers could vault right back up the polls when they play Texas in Austin Saturday.

Texas also was No. 1 in the USA Today coaches' poll and the Harris poll, with Alabama second and Penn State third. The coaches' poll and the Harris poll are used by the Bowl Championship Series to determine which teams play for the national title. The first BCS standings will be released Oct. 26.

Ohio State is 12th and LSU is 13th, a nine-spot drop after getting drubbed in the Swamp.

Despite an off week, Pitt moved up one spot to No. 23, in front of Ball State and California.

Offensive lineman Vince Vance will miss the rest of the season with a knee injury, making him the second starting left tackle the Bulldogs have lost this season. Vance will need reconstructive knee surgery and should recover for the 2009 season, coach Mark Richt said.