Oklahoma was welcomed to the SEC by being reminded of what awaits. Before Brent Venables took the SEC Media Days podium, his old pupil warmed it up for him. Venables was the co-defensive coordinator for the Sooners when Heupel quarterbacked Oklahoma to a National Championship in 2000. The third-year Oklahoma head coach has the utmost respect for what the former Sooner has accomplished as a head coach. “We’ve stayed in touch through those moments of success and some of the moments, the challenges a football season will bring you,” said Venables. “He’s a great friend. He and his wife, Dawn, and …