Indianapolis Colts quarterback Andrew Luck is being shut down due to soreness in his surgically repaired right shoulder.
Luck, who has yet to take a snap this season and only recently returned to practice, is without a timetable for his return.
The three-time Pro Bowler had been throwing every other day the past two weeks.
But Colts trainers and doctors shut down Luck on Wednesday after he required a cortisone shot and general manager Chris Ballard told reporters he is unsure when his $140m quarterback might resume throwing.
"I don't think it'll be long, but I don't want to sit here and give you an exact date and it doesn't happen and you're saying, 'What was that guy talking about?'" Ballard said.
Luck will miss his seventh consecutive game Sunday when the Jacksonville Jaguars (3-3) visit Lucas Oil Stadium.
The former No 1 overall pick had surgery in January for a partially torn labrum in his throwing shoulder and didn't return to the practice field until two weeks ago.
Without Luck, Indianapolis (2-4) have struggled offensively.
The Colts traded for New England Patriots back-up Jacoby Brissett at the beginning of September and quickly inserted him as the starter.
Brissett has thrown for 1,158 yards in five starts (231.6 yards per game) with three touchdowns and three interceptions. He has also rushed for 98 yards and three touchdowns.
