The 49ers downgraded Jennings (ankle/shoulder) from questionable to out for Sunday's game against the Cardinals.
As expected, Jennings will end up missing his first game of the season after his pair of injuries prevented him from practicing in any capacity this week. With Jennings sidelined, Ricky Pearsall will be locked in as the No. 1 target for quarterback Mac Jones, who will make a second straight start in place of the injured Brock Purdy (toe/shoulder). Jennings' absence should also open up more reps and targets for wideouts Kendrick Bourne and Marquez Valdes-Scantling.