Cardinals coach Kliff Kingsbury told the Los Angeles media that Hopkins is not ready to return from knee surgery for the wild-card game against the Rams.
Hopkins injured his knee in a Dec. 13 loss to the Rams and underwent surgery the following week to repair a torn MCL. His prognosis was six weeks.
He finished the regular season with 42 catches for 572 yards and eight touchdowns, his lowest single-season total in receptions and yards.
Watt will practice this week to see whether he can play Monday night. He had surgery to repair a dislocated shoulder on Nov. 3.