Shanahan confirmed that Griffin would start his side's opening match of the season on Monday, having completed a lengthy recovery from a serious knee injury, although Dr. James Andrews, who performed the surgery, has expressed concerns over the quarterback.
Those concerns reportedly regarded how the Redskins would use Griffin in the match, but Shanahan revealed that Andrews's misgivings were not of a tactical nature and that he was content that the 23-year-old was fit enough to play.
"He said he never said that, and he surely never said that to me. I don't think a doctor would ever say anything like that. I'm not sure a doctor would ever say anything that had to do with football," Shanahan told reporters.
"You'll have to trust us that the doctor feels good about it regardless of what those concerns were. I'm trying to be honest with you.
"[There are] certain conversations that stay between a doctor and a player or a coach and a player, this is one of those conversations."
The Redskins will face the Philadelphia Eagles in their first match of the new season on Monday.