Melton (toe) did not participate at the Cardinals' practice Wednesday, Josh Weinfuss of ESPN.com reports.
Melton suffered a toe injury during the team's 31-7 loss to Seattle in Week 2, and he is considered day-to-day. The cornerback will have two more chances to return to practice prior to Sunday's matchup with the 49ers. If he can't play this week, Kalen King would be a top candidate to draw a start at slot cornerback versus San Francisco.