Celtics Kemba Walker, Robert Williams doubtful for Game 5 Tuesday at Brooklyn

Kemba Walker, guarding James Harden (13) in Game 3, did not play in Game 4 Sunday.Elise Amendola/Associated Press

Celtics point guard Kemba Walker and center Robert Williams are listed as doubtful for Game 5 of Boston’s opening-round playoff series against the Nets on Tuesday.

Walker is dealing with a bone bruise on his left knee and Williams has been slowed by a sprained ankle and a lingering turf toe injury. Both players sat out the Celtics’ 141-126 Game 4 loss to Brooklyn at TD Garden on Sunday night.

Walker’s injury occurred during the Celtics’ Game 2 loss last Tuesday. He played in Game 3 Friday but began to experience significant soreness Saturday. Williams sat out five of the final six regular-season games because of turf toe. He was slowed by the injury in the playoffs before being sidelined by a sprained ankle in the opening minutes of Game 3.