SANTA CLARA -- Alex Smith will miss at least one game and probably more with a separated shoulder, leaving the less mobile Trent Dilfer to play behind an offensive line that has offered little protection so far this season.
Dilfer, 35, was sacked five times in Sunday's loss to Seattle and Seahawks defensive players admitted afterward they grew more aggressive with their blitzes because they knew Dilfer -- unlike Smith -- is little threat to run.
Asked Monday if that meant the 49ers would start featuring quicker passes and more three-step drops, coach Mike Nolan said it could. The question, then, is why the 49ers didn't make that adjustment during Sunday's loss.
The offense had success with three-step drops, but the vast majority of plays called for Dilfer to take five- and seven-step drops.
"We tried to get rid of it quicker and we held it a little longer," Nolan said. "That was one of the things that (offensive coordinator) Jim Hostler was talking about when we talked upstairs today. He was trying to do some things that would be more beneficial for Trent Dilfer."
The 49ers rank last in the league in passing offense and total offense, and Hostler has taken most of the criticism for the team's meager output.
Nolan, however, reassured Hostler on Monday that his job is not in jeopardy.
"He's tried to open it up as much as he can," Nolan said. "But as you saw (Sunday), we open it up one time and we jump offsides."
Nolan also said there would be no immediate changes along the offensive line, but said he would consider substitutions if the problems persist. The most obvious mix-ups are occurring on the interior of the line, where top backups Adam Snyder, Tony Wragge and David Baas all have starting experience.
It was a breakdown between center Eric Heitmann and guard Larry Allen that allowed Seattle defensive lineman Rocky Bernard to sack Smith on the third play of the game.
The hit left Smith with what the team called a grade 3 separation in his right shoulder. Smith had his right arm in a sling Monday.
Dr. Richard Marder, an orthopedic surgeon and the head of sports medicine at UC Davis Medical Center, said a third-degree separation did not require surgery but that there was clear separation between Smith's clavicle and the spot where it meets the shoulder, called the acromion. He said a Grade 3 separation also means the ligaments that attach the two bones have been torn.
The good news is that the ligaments should heal on their own and Smith should not have any long-term damage. Marder said a grade 3 separation usually requires a four- to six-week recovery period. That time frame means the best possibility for Smith's return would be Oct. 28 against New Orleans.
"If the collarbone is stable, then it's not going to be a problem," he said.
Smith, meanwhile, had a sleepless night Sunday and then went in for an MRI on Monday morning. He said he would have a physical examination of the shoulder Thursday when the swelling subsides.
"The next few days are pretty crucial to get the swelling down, to see how it feels, how it responds," Smith said.
"They won't put an exact date on it, but it will be a few weeks."