Rory McIlroy shot a bogey-free 6-under 64 at Bellerive to share a five-way lead in the BMW Championship with Gary Woodland, Wyndham Clark, J.J. Spaun, and Chris Gotterup. The group includes four U.S. Open champions atop a bunched leaderboard aided by soft conditions.

World No. 1 Scottie Scheffler struggled to a 72 while battling illness, his highest opening round since June. McIlroy rebounded from a winless four rounds at the FedEx St. Jude Championship after a four-week break, crediting work with swing coach Michael Bannon for his improved mindset.

Woodland, recovering from brain surgery and sitting at No. 31 in the FedEx Cup, holed out for eagle on the 11th and needs a top-30 finish to reach the Tour Championship. His hand-on-heart gesture before putts serves to calm his heart rate. Clark called the concentration of U.S. Open champions at 65 or better a "coincidence."