OVERLAND PARK — It was an upset for the ages, along with the signature victory during the Darren Sproles era at Kansas State, no question the marquee triumph during Bill Snyder’s first turnaround in Manhattan.In an epic 2003 Big 12 championship game at Arrowhead Stadium in Kansas City, Mo., Kansas State’s 35-7 pummeling of the No. 1-ranked Oklahoma Sooners made a mess of the national championship picture while giving the Wildcats their first conference championship since 1934, along with a berth in the 2004 Fiesta Bowl in Tempe, Ariz., against Ohio State.For Sproles, a veteran NFL running back with the New Orleans Saints, the game is burned in his memory bank. The little-big man riddled the Sooners for 235 rushing yards and 88 receiving yards — all on three screen passes — including a 60-yard catch-and-run for a touchdown from elusive quarterback Ell Roberson at the end of the second quarter, giving the Wildcats a 21-7 lead.“My crowning moment was when we beat Oklahoma in the Big 12 championship game,” Sproles said. “(The Sooners) were ranked No.