Jordan Spieth, Brooks Koepka and Matt Kuchar set the pace as Rory McIlroy staged a superb recovery from a disastrous start to the 146th Open at Royal Birkdale.
The American trio were locked together at the top of a congested leaderboard after they carded five-under 65s on an opening day which began with foul weather – and a quadruple-bogey for 1998 champion Mark O’Meara – but finished in bright sunshine and relatively benign conditions.
Paul Casey is just one off the lead with fellow English veteran Ian Poulter a stroke further back in a tie for sixth, while McIlroy’s challenge looked to have derailed when he slumped to five over after six holes before he birdied three of the last four holes to salvage a 71.
Spieth was first into the clubhouse on five under and was one of only three players on the day to get round without a bogey, gaining momentum with an early birdie at the second before two in a row capped an outward 31, and he picked up further shots at 14 and 17 but missed a great chance for another from inside 10 feet at the last.
Koepka, bidding for back-to-back major wins after landing his first at the US Open last month, made a quiet start with seven pars before getting under the card at the eighth, and he reeled off three straight birdies from the 11th before making his only mistake of the round at the 16th.
But he responded by holing his bunker splash-out for an eagle at the long 17th to join Spieth in the lead, although both looked likely to be upstaged by Kuchar when he stormed to the turn in just 29 blows with his fifth birdie at the ninth.
However, the former Players champion could not convert a number of further chances on the inward half and settled for nine pars to remain tied for the lead, and one clear of Casey and Charl Schwartzel.
Casey celebrates his 40th birthday on Friday and continued his excellent form in the majors this season with a five-birdie opener, his only blemish coming when he took three putts to get down at the 11th.
“Apparently life begins at 40 so maybe that’s a good omen for me,” said Casey. “With everyone saying bad weather is coming, it was a case of making hay while the sun shines so it was important to capitalise on the conditions.”
Schwartzel was the clear winner of his threeball with McIlroy and world No 1 Dustin Johnson, the South African scrambling hard to get to the turn in level par before birdies at 10, 13, 17 and 18 hoisted him into contention.
Poulter teed off in the worst of the conditions early on but he defied the elements and, as the clouds gave way to sunshine mid-morning, he wielded a hot putter only 25 times and mixed four birdies with just one dropped shot to set the early target at three under.
Justin Thomas, sporting a classic collar-and-tie, produced golf to complement his stylish outfit and an eagle at the 17th lifted him alongside Poulter, and they were later joined by English journeyman Richard Bland, rising Canadian star Austin Connelly, Charley Hoffman and Rafa Cabrera Bello.
Defending champion Henrik Stenson was happy with a solid 69, while McIlroy and Johnson (71) both have ground to make up early on Friday after both failed to break par.
For McIlroy, it could have been far worse as his all-round game deserted him from the off, and he did well to limit the damage to a bogey at the opening hole before he dropped four strokes in a row from the third.
He looked a forlorn figure when another wayward tee shot at the eighth finished in thick rough, but he holed a superb 20-foot putt to save par and looked close to his best after the turn as he finally got a birdie on his card at the 11th.
McIlroy battled hard and two-putted the 15th and 17th for birdies, and the packed grandstands around the 18th green gave him a generous ovation when he knocked in another from 15 feet to revive his hopes of a first major win since the 2014 PGA Championship.
Another to finish with a flourish was Masters champion Sergio Garcia, who was five over with two to play after a double-bogey at 16 before his first birdie of the day at 17 was followed by his second at the last as he signed for a 73.