DENVER -- After missing most of Thursday's practice with a sore throwing shoulder, Denver Broncos quarterback Brian Griese was a full participant in Friday's workout and was expected to start on Sunday in Seattle.

The Broncos added Griese to their injury report on Friday morning, listing him as questionable.

An hour later, however, Griese had no obvious discomfort during a 75-minute workout. Coach Mike Shanahan said he was confident that, barring any setbacks, Griese will play against the Seahawks.

Griese has had surgery twice on his shoulder, after the 1999 and 2000 seasons.

Shanahan said Griese reported soreness in his shoulder after Sunday's 20-6 win over Kansas City. The injury likely occurred in the first half, since Griese threw only five passes after intermission. For the game, he was 11-of-20 for 121 yards with one touchdown and one interception.

"It was sore after the game, but we didn't think it was anything that would keep him from playing," Shanahan said Friday. "He couldn't practice (Thursday). He just took a few reps and it was sore. That's why we put him on the questionable list. I wasn't really sure where we'd be at (Friday).

"But he was able to make it through practice and he was effective. So if there's no setback, then he'll be able to go Sunday."

If Griese had been unable to practice Friday, Shanahan said, the Broncos would have prepared backup Gus Frerotte for a starting role.

"If you don't practice Thursday and Friday, then you don't start," Shanahan said. "But he was able to go through the whole practice, and he practiced well."

Offensive guard Dan Neil, hobbled by a sprained left ankle, also practiced Friday. He, too, was listed as questionable on the injury report.

The Broncos spent much of Friday's practice working in front of speakers blaring simulated crowd noise, as they typically do before a road game.