From: CBS Sports

Jets wide receiver Brad Smith has a concussion as a result of a vicious hit he took from San Francisco’s Patrick Willis, and his status for New York’s game against Buffalo on Sunday is uncertain. Jets coach Eric Mangini, who confirmed the head injury Thursday, said Smith has only been participating in light workouts during practice. “There’s improvement,” Mangini said before practice. “If he does anything at all, it will be light stuff today. Really, it’s the same process we’ve been doing.”