Mayo (knee) has been ruled out for the season, ESPN's Adam Schefter reports. Mayo was carted off the field Sunday against the Bills after suffering a lower-leg injury. He underwent an MRI on Monday, and while the team has not provided an official diagnosis, Mayo's injury is severe enough that it will keep him out for the remainder of the 2014 season. This is the second consecutive year in which Mayo has suffered a season-ending injury, as he was lost to a torn pectoral a year ago to the day.