Illinois - American Steve Stricker withdrew from the BMW Championship after Friday's second round due to a sore neck, putting his participation in the season-ending Tour Championship in jeopardy.
"Steve has been battling some neck pain the past few days and the discomfort became more severe today," Stricker's representative, Jon Heaton, said in a statement.
"After consulting with his doctor, he has decided to rest at home for a few days in hopes of regaining full strength for the Tour Championship next week."
After labouring to a five-over-par 76 at Cog Hill Golf and Country Club on Thursday, world number five Stricker had bounced back with a 70 on Friday before pulling out of the third of four lucrative FedExCup playoff events.
Only the top 30 after Sunday's final round at Cog Hill qualify for the season-ending Tour Championship next week in Atlanta, where a $10 million bonus will go to the overall points leader.
Stricker, who has won twice on the PGA Tour this season, had been well positioned to make a run for the big prize, occupying eighth place in the FedExCup standings before the start of the BMW Championship.