The Big 12 has no more undefeated teams. You can thank Iowa State and freshman quarterback Brock Purdy.

Purdy made his first start of the season Saturday and led Iowa State to a 30-14 win over No. 6 West Virginia. Purdy came on in relief of Zeb Noland a week ago and threw five touchdowns in a road win over Oklahoma State. Against West Virginia he was 18-of-25 passing for 254 yards and three touchdowns, outplaying West Virginia’s Heisman contender Will Grier.

Iowa State’s defense gets a ton of credit too. The Mountaineers scored 35 or more points in each of their first five games of the season. Iowa State pressured Grier all evening and never let him get comfortable. Grier was just 11-of-15 passing for 100 yards and a touchdown and an interception. The Mountaineers converted just one of 11 third-down opportunities and had to punt eight times.

ISU took a 28-14 lead in the fourth quarter when Purdy found Deshaunte Jones for a fantastic 32-yard touchdown. Grier threw an interception on the next possession forcing the ball deep down the middle of the field. After Iowa State punted, Grier was sacked on consecutive plays. The second was for a safety and the game’s deciding margin.

The Cyclones’ win undoubtedly brings back memories of a certain 2011 win in a night game in Ames. Seven years ago Oklahoma State visited Iowa State with dreams of a national championship. The Cyclones upset the Cowboys and prevented OSU from going to the BCS championship game.

Or, if West Virginia fans prefer, the loss to Iowa State is a sign of things to come. Oklahoma made the College Football Playoff with a talented senior quarterback at the helm in 2017 despite losing to Iowa State.

The Big 12 is all jumbled

The Big 12’s nightmare scenario may be upon us. After re-instituting the conference title game in 2017, Oklahoma saved the conference from disaster by beating TCU for the second time to get a playoff berth.

With every team in the conference proving fallible through the first seven weeks of the season, there’s no clear frontrunner. Texas is now atop the conference standings at 4-0. The 6-1 Longhorns have reeled off six-straight wins after a Week 1 loss to Maryland. But starting QB Sam Ehlinger suffered a shoulder injury in a 23-17 win over Baylor that came down to the final play. Texas may be playing better football, but the Longhorns are vulnerable.

So is Oklahoma, who fired defensive coordinator Mike Stoops after losing to Texas a week ago. The Sooners were off Saturday. They’re now in a three-way tie for second with the Mountaineers and Texas Tech, who got a key win Thursday night on the road at TCU.

At 4-2, Tech is out of the playoff conversation, leaving Texas, Oklahoma and West Virginia as the conference’s playoff hopefuls. Do you trust any of those three teams to get through the rest of the season without another loss? We don’t, especially after West Virginia’s performance on Saturday night. And that’s not good news for the conference’s playoff hopes.

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Nick Bromberg is a writer for Yahoo Sports.

Follow @NickBromberg on Twitter

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