Long suffered tendon damage in the foot during last Sunday's win over the Jets.
"That's my guy," Bears quarterback Mitchell Trubisky said of Long after the Jets game.
"He's always had my back, and I can't say enough about Kyle and how much he loves this organization and the game of football. To see a guy go down like that, it hurts, and we just try to pick him up and rally around him any way we can. He knows we love him, and we're just going to hope for the best."
Long exited the in the fourth quarter after he injured his foot during a 1-yard gain by Bears running back Jordan Howard. Long was unable to put pressure on his right foot as he left the field with the help of team doctors. He was immediately carted back to the locker room.
Long is no stranger to injuries.
Chicago's first-round pick in 2013, Long suffered a gruesome ankle injury in 2016 that cost him the final eight games that year and the first two games of the 2017 season.
Last year, Long missed six games altogether with a variety of ailments. Long underwent neck, shoulder and elbow surgeries in the offseason, but he returned in time to start the Bears' first seven games this season.
Long is under contract with the Bears through 2021. The veteran offensive lineman's $6.9 million base salary for next season becomes fully guaranteed on the fifth day of the 2019 league year.
"He's already been through so much already, and it sucks to see Kyle go down like that," Bears left tackle Charles Leno Jr. said. "We don't know the severity of it yet, so we're just trying to support him back there and give him some love because I know what he's been through."
Chicago also announced that promising rookie defensive tackle Bilal Nichols did not accompany the team to Buffalo because of a knee injury.