Seatrunk said in a statement Monday that he's fully prepared to take the next step toward realizing his goal of playing in the NFL.
Coach Art Briles says he appreciates "the dedication and energy" that Seastrunk brought to the team.
The Oregon transfer played two seasons at Baylor, and was the first player in school history with two 1,000-yard rushing seasons. He ran for 1,177 yards and 11 touchdowns in 11 games this season, missing nearly three full games because of a groin injury.
The Big 12 champion Bears return Shock Linwood, who ran for 881 yards and eight TDs as a freshman this season.