Since falling to Utah on Saturday, USC football coach Lincoln Riley had been MIA with an undisclosed illness. Riley was back at practice on Wednesday, and it has been revealed that he is being treated for pneumonia, according to Ryan Young of Rivals.

Riley had previously missed his weekly radio appearance on “Trojans Live” on Monday due to feeling under the weather, and USC football even worked with NCAA compliance to make senior offensive analyst and quarterbacks coach Kliff Kingsbury their acting on-field assistant in Riley's absence.

Riley's absence couldn't have come at a worse time for USC football, as the team is mired in a two-game tailspin that has likely cost them a shot at the College Football Playoffs. Before Saturday's loss to the Utah Utes, the Trojans were blown out by Notre Dame 48-20.

With six Pac-12 teams in the Top-25 and several of them likely to beat each other, the Trojans do still have a shot at the Pac-12 Championship game in Las Vegas. Only the Washington Huskies remain undefeated, while USC football sits only one loss behind the Oregon Ducks, Oregon State Beavers, and the Utes. The UCLA Bruins join the Trojans as the conference's other two-loss program.

Fortunately for USC football, Lincoln Riley gets to ease his way back into action this Saturday, as they take on the Cal Bears. Cal has struggled again this season under Justin Wilcox, sitting at 1-3 in conference play with their lone win being a nail-biting 24-21 win over the 1-4 Arizona State Sun Devils.

It's not clear exactly what treatment Riley has received for his pneumonia, but he is feeling well enough that he will hold his regular media availability over Zoom on Thursday.