Mason Crosby’s mighty leg lifted Colorado into a Top 25 ranking and the lead in the Big 12 North. Now it’s time to bring on the challengers.

Crosby kicked a 50-yard field goal with six seconds left to give Colorado a 23-20 victory at Kansas State and – combined with Missouri’s 13-3 loss at Kansas University – a one-game lead in the North.

The Buffaloes, who moved into the Associated Press rankings at No. 25 on Sunday, conclude the regular season with games against Missouri, Iowa State and Nebraska – the three teams immediately behind them in the North standings.

Despite its loss, Missouri still controls its own fate in the North race. With consecutive victories against Colorado, Baylor and Kansas State, the Tigers would win the North.

First, they have to find consistency on offense – and that means figuring out how to free up Brad Smith.

Smith was held to 84 yards of total offense against Iowa State two weeks ago, then set a school record with 480 yards last week against Nebraska. He totaled 179 yards against Kansas, including a season-low 38 yards rushing. In his last three games against Kansas, all Missouri losses, Smith has totaled 30 yards rushing.

“I think Brad did all he could do,” Missouri running back Tony Temple said. “But one man can’t do too much. We all have to make plays and stay together.

“Brad’s only one person, you can’t put it all on one person. It’s the coaches, the team, it’s everybody.”

Iowa State beat Texas A&M, 42-14, to stay two games back of Colorado, and Nebraska dropped to two games back with a 31-24 loss to Oklahoma.

The Cyclones (5-3, 2-3 Big 12) have won back-to-back games after losing their first three Big 12 contests. Nebraska (5-3, 2-3) has lost two straight.

No. 2 Texas maintained control of the South Division by rallying from 19 points down to beat Oklahoma State, 47-28. The Longhorns have a one-game lead over Texas Tech and Oklahoma, plus tiebreakers over both teams.

The remainder of the Longhorns’ schedule consists of Baylor, Kansas and Texas A&M, and Texas coach Mack Brown expects to get each team’s best shot.

“The higher you get, the more you’re exposed, and people are trying to beat you,” Brown said. “That’s just part of the life at this point in the season.”

Texas Tech got a lift from its defense to get past Baylor. The Red Raiders got their first Big 12 road shutout in a 28-0 win in Waco.

Baylor coach Guy Morriss decided to take a made field goal off the board on the Bears’ first possession of the second half when the Red Raiders were called for a roughing-the-kicker penalty that moved the ball to the two-yard line. Paul Mosley was stuffed on the ensuing fourth-down play.

“I was trying to get them cranked up, anything to get them going,” Morriss said. “I’m not so sure three points would have helped us there.”