Josh Brock, who sat out all of 2004 due to a shoulder injury and has missed all of this season due to a concussion, returned to full contact practice Tuesday but didn't dress for Wednesday's practice.
"I don't know if it was a concussion, but he got dinged enough where he didn't practice today," Richt said.
Brock, a guard, declined to speak to members of the media after practice. He had just recently expressed optimism about his return to the field.
"For me to be back out there, I can't explain how happy I was," he said last week after returning to limited action. "It was pretty bad there for a little while (sitting out). It got me real down. It'll be a good time for me to get back in the swing of things."
Brock, who started 12 games in 2003, suffered severe nausea and problems concentrating for almost a month after suffering his third concussion during fall practice.
If he is forced to quit football, he will join Bartley Miller, who also started in 2003 before missing all of 2004 due to shoulder injuries. Miller's shoulder problems didn't allow him to return this season.