-- For the first time, the Baltimore Ravens publicly acknowledged today that season-ending surgery might be necessary to correct all-pro linebacker Ray Lewis's injured left shoulder. Also, quarterback Chris Redman will miss at least this week's game and may require back surgery.

"That's always a possibility in both cases," trainer Bill Tessendorf said.

Lewis partially separated his shoulder Oct. 6 against the Cleveland Browns. Tessendorf said several Ravens with similar injuries in the past have mended without surgery and that an exam on Lewis today showed the swelling had gone down.

The problem, he added, is not weightlifting but shifting his weight in awkward positions at home, sometimes while asleep.

"We'll do a bit of modification in his activities," Tessendorf said. "The realm of improvement usually is between three to six weeks."

And Lewis is starting the fourth week.

"I don't think we're in that window yet," Coach Brian Billick said. "But you can't rule [surgery] out. If it's a season deal, then that's the challenge we'll face."

All Lewis would say was, "I don't know nothing."

In addition to Redman and Lewis, defensive end Michael McCrary (knee) will miss Sunday's road game against the Atlanta Falcons. This will be Lewis's fourth straight week on the sideline and the second for Redman and McCrary.

In their first two games without Lewis, a last-second loss to the Indianapolis Colts on the road and a victory over the Jacksonville Jaguars at home, the defense generally played well. However, the Pittsburgh Steelers drove 68 and 80 yards on their first two possessions Sunday and grabbed a 28-3 halftime lead before breaking a first-place tie with the Ravens in the AFC North with a 31-18 victory.

Billick challenged the entire team at halftime and said the defense holding the Steelers to one first down in the final 30 minutes was "magnificent."

Redman, who lately had played well in his first season as the starter after being chosen in the third round of the 2000 draft, experienced back trouble during his college career at Louisville. Never, he said after the game Sunday, had the pain run down his leg and his foot and his toes become numb. He was unavailable to comment today.

"Any time you've got numbness," wide receiver Brandon Stokley, Redman's road roommate, said, "that's frightening. He wanted to play, but when you can't plant on your foot, that's going to hurt the team."

Redman saw a back specialist today after his MRI exam and Tessendorf said the treatment course "may take as long as 14 days."

"At this point," Tessendorf added, "he's improving with the current medication and treatment, limited activity. As things develop, we'll see."

Backup quarterback Jeff Blake will have a full week of practice rather than almost no on-the-field preparation as was the case before the Steelers' game. When Redman was unable before the game to shake the numbness in his right foot he first experienced late Friday night, Blake started and completed 29 of 50 passes for 298 yards and a touchdown.

He also was intercepted three times, with the last two coming after the Ravens narrowed their 25-point halftime deficit to 13 early in the fourth quarter.

"You can't imagine the difficulty of not taking any reps during the week," Billick said.

Blake throws harder than Redman and is more mobile, and the Ravens will adjust their game plan.

"It doesn't matter who the quarterback is," Stokley said. "We've got enough trouble handling our own jobs."

Ravens Note: The Ravens expect backup defensive back James Trapp to be fined after being ejected Sunday for an incident with Steelers wide receiver Plaxico Burress. Replays indicated Trapp brought his foot down on Burress's helmet. Burress also was thrown out.

Linebacker Ray Lewis likely will miss his fourth straight game Sunday when the Ravens play the Falcons in Atlanta.