Lee Westwood made an impressive start to his US PGA Championship campaign to earn a share of the lead alongside Ryan Palmer and Kevin Chappell at Valhalla.
The 41-year-old kicked off his round with a double bogey on the opening hole, but he quickly found his best form before finishing with five birdies in six holes to climb to six-under-par.
Palmer had held the lead on his own at one stage on Thursday before a mistake saw him slip back into the pack, while Chappell carded his own 65 with a bogey-free round.
World number one Rory McIlroy made a number of errors in the middle of his round to fall to level-par, but five birdies late on eventually saw him climb to within one stroke of the lead next to Edoardo Molinari, Jim Furyk, Henrik Stenson and Chris Wood on the leaderboard.
Tiger Woods could only manage a three-over 74, meaning that the American faces a battle to make the cut in the second round, while defending champion Jason Dufner was forced to pull out with a neck injury.
Callum Mulvihill
