Melton (heel) did not participate in Thursday's practice, Josh Weinfuss of ESPN.com reports.
Melton was a limited participant in Wednesday's practice, but he apparently suffered a setback with the heel injury he likely sustained during the Cardinals' Week 12 overtime loss to the Jaguars. The downgrade in practice participation is a bad sign for the starting cornerback's chances to suit up for Sunday's game against the Buccaneers.