Brandon Weeden threw three touchdowns and No. 6 Oklahoma State extended its road winning streak to nine games with a 45-24 victory over rival Missouri on Saturday.

Joseph Randle ran for three scores and caught another for the Cowboys, who are 4-0 in conference play for the first time since 1940.

Oklahoma State (7-0, 4-0 Big 12), ranked fourth in the initial BCS standings, boosted its national championship hopes with a quality win over a Missouri (3-4, 1-3) team that had won 10 straight at home.

And the Cowboys did it mostly without reigning Biletnikoff winner Justin Blackmon, who was held out as a “precautionary measure” after suffering a head injury. He had eight catches for 54 yards and a first-quarter touchdown.

Weeden was 24-of-36 for 270 yards and three scores in the first half, but he threw just 13 passes in the second half as the running game (204 yards) took charge.

So did the Cowboys’ opportunistic defense, which came up with four turnovers that swung the momentum every time Missouri appeared to have life. Shaun Lewis’ interception of a batted ball set up Randle’s 16-yard touchdown run that gave Oklahoma State a 31-17 lead midway through the third.

Randle’s 59-yard touchdown run, which came three plays after Lewis recovered quarterback James Franklin’s fumble at the Cowboys’ 21-yard line, made it 38-17 lead with just over a minute remaining in the third.

Franklin threw three interceptions for Missouri, which was seeking to win consecutive games for the first time this season.