Casey was starter last year @ Nebraska after transferring from Texas. New HC Rhule brought in transfer QB Sims from Georgia Tech to compete as starter. Thompson was still recovering from surgery so wasn't able to fully compete this Spring and it seems Rhule is leaning toward Sims as starter. Two other Nebraska QBs have already entered the portal this week and now possibly Thompson. Tough QB situation for a new HC. Thompson will be a grad transfer, thus immediately eligible to play.