Wallace was selected by the
Dallas Cowboys in the tenth round (259th) of the
1971 NFL draft. As a rookie, he was switched from the
defensive to the
offensive line, becoming a member of the
Super Bowl VI winning team under coach
Tom Landry. He was mainly a backup that rotated from
offensive tackle to
offensive guard throughout his professional career. In
1972, he left abruptly during training camp after reporting 36 pounds overweight, stating that he was considering retirement, but went on to have a change of heart and returned to make the final roster. The next year, he suffered a back injury and was placed on the
injured reserve list, but was able to return to play in 12 games. In
1974, he underwent spinal surgery. He was released on September 14,
1975. ==Personal life==