Phil Mickelson has prioritised the Ryder Cup over the PGA Tour's season-ending FedEx Cup by withdrawing from the BMW Championship after round two.
The American, 44, was tied 63rd, 14 shots off the lead after a six-over 76.
Mickelson needed a top-four finish to have a chance of qualifying for next week's Tour Championship in Atlanta.
"Without a chance to contend at the Tour Championship, the most important thing is to prepare for the Ryder Cup," said the five-time major winner.
Mickelson has played 38 matches in nine Ryder Cup appearances, winning 14, losing 18 and halving six, to amass 17 points.
He has been on the winning side just twice, in 1999 and 2008.
|Mickelson's Ryder Cup record|
|Years played||1995, 97, 99, 2002, 04, 06, 08, 10, 12|
Spain's Sergio Garcia leads the BMW Championship on eight under, one shot ahead of American Ryan Palmer and two clear of his Northern Ireland Ryder Cup team-mate Rory McIlroy.
It will be the first time Mickelson has missed the Tour Championship, and a chance to win $10m (£6.1m) as the overall winner of the FedEx Cup.