Indianapolis Colts quarterback Andrew Luck is set to miss between two and six weeks of action with a lacerated kidney.
Luck sustained the injury in the fourth quarter of the Colts' 27-24 NFL victory over Denver Broncos on Sunday, with the team confirming his absence in a news release.
As well as the lacerated kidney, the Colts revealed a partial tear in Luck's abdominal wall, but he will not require surgery.
"The injuries happened at the end of an early fourth quarter scramble when Andrew was doing everything he could to get us the win," head coach Chuck Pagano said.
"Andrew was sore after the game and was feeling a little worse Monday afternoon so we sent him to get tests."
Veteran Matt Hasselbeck is set to start at quarterback, and Pagano is confident the 40-year-old can step up in Luck's absence.
"It's way too early to guess how long Andrew will be out," Pagano added.
"We're going to keep listening to the doctors and evaluating his progress on a week by week basis.
"We've got all the confidence in the world in Matt Hasselbeck and we're not going to put Andrew back out there until he's healed and ready to go."