Head coach Jonathan Gannon told reporters Monday that Melton is in concussion protocol, Darren Urban of the Cardinals' official site reports.
The rookie corner made his NFL debut Sunday and recorded two total tackles on 27 total snaps (17 on special teams and 10 defensive), but considering Gannon's comments, it appears Melton sustained a concussion at some point. Melton's practice participation will be something to monitor as the week progresses, and if he's forced to miss time, expect Kei'Trel Clark and Darren Hall to see more work in Arizona's secondary.