"But I'm not sure he would, which I would understand," Shanahan said. "But I think that's why we're talking about hypothetical situations. I don't think that would happen. But if he was interested in that, obviously, that'd be a possibility."
Shanahan had a different take on McNabb's version of how the quarterback was informed of his demotion last week.
McNabb said on his weekly radio show Tuesday that he was frustrated Shanahan didn't inform him until last Thursday that Rex Grossman would replace him as the starter. McNabb, who still insisted he'd like to stay in Washington next season, said information was leaked to the media in advance of the move.
But Shanahan said he told nobody before he spoke with the quarterbacks.
"People might have speculated on it, but there was nothing else," the coach said.
McNabb also said Shanahan failed to tell him he would be the team's No. 3 quarterback for the final two games.
"I did talk to Donovan (about) exactly what his role was gonna be, just like I shared with (reporters)," Shanahan said. "That he was gonna be No. 2 (against Dallas), and then the next two games he was gonna be No. 3 -- and I explained why.
"With John Beck getting the reps, just like I did to you guys (reporters), I went into detail about that. I really felt that after I was done, it was a good conversation and we'd go from there."