Jimmy Walker ended day one of the US PGA Championship with a one-stroke lead and Henrik Stenson shone once again, but there was misery for Dustin Johnson and Rory McIlroy at Baltusrol.
Walker was among a host of early starters to prosper under sunny skies before the weather gradually worsened in New Jersey, with a passing storm bringing rising winds and a burst of rain late in the day.
Martin Kaymer and Stenson defied the trickier conditions to card impressive respective scores of 66 and 67. The former joined the unheralded duo of Emiliano Grillo and Ross Fisher in a share of second and Stenson is also very much in contention as he seeks to secure a second successive major after his stunning victory in The Open a fortnight ago.
Henrik Stenson's last seven Major rounds:-- The European Tour (@EuropeanTour) July 28, 2016
69, 69, 68, 65, 68, 63, 67
27 under par! pic.twitter.com/qLOph2zIXT
Yet Walker's five-under 65 was enough to keep the American at the summit of the leaderboard, on a day when two of the pre-tournament favourites found life much tougher.
U.S. Open champion Johnson slumped to a woeful 77 and McIlroy - a two-time winner of this event - could only muster a 74.
Phil Mickelson, so impressive en route to a second-placed finish behind Stenson at Royal Troon and the champion when the US PGA was last held at Baltusrol in 2005, looked set to suffer a similarly disappointing opening round, but picked up three shots in his last seven holes to salvage a 71.
Jordan Spieth enjoyed a similar recovery, birdieing 16 and 18 to complete a level-par 70. The latter's only blemish was a double bogey at the seventh.
If Spieth could be satisfied with his finish, world number one Jason Day was certainly in a confident mood after beginning his title defence with a 68 in the company of Mickelson and McIlroy. Also at two under - a stroke behind Stenson, Harris English, James Hahn and Andy Sullivan - were the likes of Rickie Fowler and Louis Oosthuizen.
Walker has struggled for much of 2016, but cited increased confidence with the putter as a key factor in his impressive performance on Thursday.
By contrast, McIlroy was left to bemoan his efforts on the greens, with a tally of 35 putts ensuring he was unable to take advantage of the relatively benign conditions that greeted those out in the morning.
Kaymer, US PGA champion in 2010, took heart from staying in touch with the leader as the winds rose.
"The last six or seven holes were really tough," the German told Sky Sports. "To finish with six pars was very solid. I had a couple of really good up-and-downs."
Dustin Johnson is T143 after shooting 77.-- PGA TOUR (@PGATOUR) July 28, 2016
It's his highest round since January.
Golf is hard. pic.twitter.com/7OPXPc8i50