Sam Darnold has mononucleosis and will miss multiple games, including Monday night against the Browns, Jets head coach Adam Gase told reporters on Thursday.
Darnold missed Wednesday's practice with what was called strep throat. Gase said the Jets hope to get Darnold back in Week 5 after the team's bye.
"I don't want to put predictions on anything," Gase said of Darnold's timeline to return. "I'm just glad we've got the bye week when we do."
Gase said he went to Darnold's residence with offensive coordinator Dowell Loggains and a trainer to break the news to their quarterback and that Darnold had been alarmed by the amount of weight he had recently lost.
"The way he reacted to it last night, he went right into, 'What are my solutions?' " Gase said about Darnold.
Gase told the team of the situation this morning in a meeting. Trevor Siemian will start in Darnold's place.
"Our next man philosophy does not waver," Gase said. "It's about everybody doing their job. That's why Trevor is here."
In addition, running back Le'Veon Bell is getting an MRI on his sore shoulder and will not practice on Thursday, Gase said.
