The NFL's second-leading rusher left Redskins Park during practice, wearing a gray hooded sweatshirt and burgundy sweatpants as he stepped into his Maserati.
"I was hoping today that there would be a little more optimism, and there's not," coach Jim Zorn said. "He's still questionable. I would say there's no change today. I was looking for another jump, but there wasn't."
Portis sprained his left knee in the 23-6 loss to the Pittsburgh Steelers before last week's bye.
With Portis ailing, Ladell Betts appears set to start Sunday. Betts has missed the last three games with a sprained knee, but he was on the field in steady rain for Thursday's practice.
"Betts looked good," Zorn said. "He's got a brace on but made some cuts. That was encouraging."
Shaun Alexander would start if both Portis and Betts are unable to play.
Zorn also said he doesn't expect defensive tackle Anthony Montgomery (Achilles) to play and was pessimistic about Marcus Washington (shoulder). The coach said he expects Shawn Springs (calf) to be available, but Springs did not practice and said he doesn't expect to practice again Friday. If Springs doesn't play, new signing DeAngelo Hall would have a greater role in his Redskins debut.
"I don't believe I'm going to activate him," Zorn said. "He's so far behind. I'm just glad he's out there."