| | Big 8 grid notes Associated Press The key to Nebraska's game with Oklahoma for the Big Eight football championship Saturday will be ball control, Cornhusker Coach Bob Devaney says. "Their offense is geared to ball control,", he said Wednesday. "Against teams like Oklahoma State, Iowa State and Kansas State, who threw the ball a lot, you figure to get the ball a few times through unscheduled means such as pass interceptions." "But a team like Oklahoma," he added, "you've just got to stop them on defense or hope they'll fumble. This is the first ball control type team we've faced since we played Colorado." At Oklahoma, Coach Chuck Fairbanks made two defensive changes. Linebacker Steve Casteel, injured since the Texas game, went back to his starting position, and strong-side- linebacker Jon Milstead was moved up to the first team, Fairbanks said the Sooners had a good practice and showed *a lot of enthusiasm and were much sharper on their assign-| ments."