FLORHAM PARK, N.J. (AP) New York Jets quarterback Sam Darnold has mononucleosis and will miss at least the team's game against the Cleveland Browns on Monday night.
Coach Adam Gase says Thursday that Trevor Siemian will start in Darnold's place.
Gase says the team learned of Darnold's diagnosis Wednesday and he went to the second-year quarterback's home to personally deliver the news to him. The coach says Darnold's biggest concern is weight loss. Gase adds Darnold has already lost about 5 pounds.
Darnold missed practice Wednesday when the team sent him home because he was feeling ill. Team doctors later told him that antibiotics weren't working as quickly as expected, leading to the diagnosis.
The Jets will need to sign a backup for Siemian or elevate Luke Falk from the practice squad.