For the third consecutive day, the Heisman Trophy winner didn't participate in an Oklahoma non-football activity due what is believed to be an unknown sickness. On Friday, Mayfield did not attend a media availability in downtown Los Angeles.
He has "no voice to speak of," said a team spokesman.
Another source termed Mayfield's affliction, "a little cold. Nothing major."
Three days before the College Football Playoff semifinal against Georgia at the Rose Bowl, that's not good news. Mayfield was the runaway Heisman winner, leading the nation in passing efficiency each of the last two years.
Going into his last college game, Mayfield is widely considered one of the best Sooners' players in history.
Georgia defensive end Jonathan Ledbetter is hopeful to see Mayfield suit up.
"I hope he (Mayfield) does get to play," Ledbetter said. "I actually played in a game I did have a fever. I just put on a thermal. I kind of tried to sweat it out. I was in the hotel coughing, throwing up. I still came out and played. If something is broken, I actually still might play. Until I can't play, I'm going to play."
Oklahoma officials wouldn't specify Mayfield's illness, only that it is legitimate. When asked about their quarterback's health Friday, Oklahoma players and coaches, to a man, said, "You'll have to ask Coach Riley."
Coach Lincoln Riley wasn't at Friday's availability that was supposed to feature Mayfield, other Sooners offensive players and Georgia defensive players.
Other than that, Mayfield's exact condition isn't known. He has practiced to some degree this week, but wasn't at a Wednesday media availability at Disneyland.
Friday's availability at the L.A. Hotel Downtown is about a 15-minute walk from Oklahoma's team hotel.