Coach Mike Munchak said he didn't know the severity of the concussion because the player was still being evaluated.
McCourty was hurt when he and linebacker Akeem Ayers teamed up to tackle Bills tight end Lee Smith. McCourty lay on the field for several minutes before eventually getting up on his own and walking off to the sideline late in the first quarter.
He was then escorted by a Titans trainer to the locker room at the end of the quarter.
Receiver Nate Washington hurt his left ankle in the third quarter while making a 12-yard catch at the Bills 8-yard line. Washington limped off the field, but returned for a few plays. He made what proved to be a critical 12-yard catch to convert a third-and-8 situation early in the fourth quarter. Rob Bironas capped the drive by hitting a 44-yard field goal that put Tennessee ahead 23-10.
Munchak elected to sit Washington after that catch in fear he could aggravate the injury.
"It's not a real bad one, but we had to tell him he was done for the day because we didn't want to take a chance and lose him for two to three weeks," Munchak said of the team's leading receiver.
Bills rookie cornerback Aaron Williams did not return after hurting his left knee in the third quarter.
Tight end Scott Chandler hurt his left ankle while being gang-tackled and had the ball stripped out of his hands early in the third quarter. Chandler returned to make a 15-yard catch later in the quarter but came up limping and was sidelined for the rest of the game.
Coach Chan Gailey had no update on his injured players, except to say Williams was having tests and Chandler was hobbling.