Hideki Matsuyama withdrew from the BMW Championship with a lower back injury Friday, one day after he shot an opening-round, 5-under 67 to sit one shot off the lead.
Matsuyama has dealt with back and neck injuries for the past few years.
Matsuyama recorded the 10th PGA Tour title of his career by winning last week's playoff opener, the FedEx St. Jude Championship. That victory allowed him to soar into third in the FedEx Cup standings. He is assured of having a strong position for next week's staggered start at the Tour Championship, where the winner will receive a $25 million bonus.
The tour announced Matsuyama's withdrawal shortly before his morning tee time and later released a statement from the 32-year-old Japanese player, who is ranked No. 6 in the world.
"I am disappointed to have to withdraw from the BMW Championship after experiencing lower back discomfort while warming up this morning, which made it impossible to play," Matsuyama said. "Thank you to BMW and the Western Golf Association for a great experience here at Castle Pines."
Information from The Associated Press and Field Level Media was used in this report.