Defending champion Justin Thomas was in a familiar position at the top of the leaderboard as the first round of the US PGA Championship got under way at Bellerive Country Club.
The American arrived in St Louis off the back of a victory at the WGC-Bridgestone Invitational last week and he turned in 32 to get to three under early on Thursday.
That put him alongside countryman Stewart Cink, with a high-class chasing pack just one off the lead including Spaniard Rafa Cabrera Bello, Finn Mikko Korhonen, American Pat Perez and England's Ian Poulter.
Rickie Fowler, Billy Horschel, Hideki Matsuyama and Webb Simpson were also at two under.
Thomas' three birdies came via some exquisite iron play as he put approaches to inside eight feet on the 11th, 12th and 15th, while 2009 Open champion Cink made a hat-trick of gains from the 11th in his first seven holes.
Poulter had set the early pace as he sandwiched a stunning approach to the 12th with birdies from around 12 feet on the 11th and 15th but he dropped a shot on the 17th.
Playing partner Matsuyama birdied the 17th and first with Fowler - the third member of one of the morning's marquee groups - doing the same after a birdie on the 14th and bogey on the 16th.
Cabrera Bello parred his first seven holes but then hit a nice pitch into the par five 17th, and a stunning approach to six feet on the next had him at two under.
Korhonen made a fast start, birdieing the second and fifth, while Perez had gains on the 11th and 17th.
Horschel had three birdies and a bogey on the front nine, while Simpson made gains on the 12th and 17th.
There was then a large group at one under including Ryan Fox, Shane Lowry, Branden Grace, Julian Suri and Shubhankar Sharma.
