Paul Casey finished last year's US PGA Championship after two days with a round of 85, but today he began the final major of 2013 with a superb 67 at Oak Hill.
The former world number three, down at 169th in the rankings after struggling for form and fitness before winning the Irish Open in June, carded five birdies and two bogeys to finish three under, two behind clubhouse leader Jim Furyk.
World number one Tiger Woods, seeking his 15th major title but a first since the 2008 US Open, was two under after six holes but eventually finished one over after a double-bogey six on the ninth, his final hole.
Casey had started inauspiciously with a bogey on the 10th and followed that with eight straight pars to the turn, but he then birdied five of his next seven holes and made sure to check out his name high on the leaderboard as he finished.
"It's a while since my name has been up there," said the 36-year-old, who broke his collarbone snowboarding at the end of 2011. "It felt good.
"You don't realise how much you miss something until it's gone and sitting on the sofa watching the big events of the last year and a half I have had lots of extra motivation to get back.
"It added another reason for getting out there and working hard and things like Justin (Rose) winning the US Open is good fuel for the fire.
"I got a bit lucky today with a couple of monster birdie putts from 50ft and 33ft on the fifth and seventh, but we're off and running. I knew I had to get something going after the turn because I had got through the tough part of the course."
The early starters enjoyed perfect scoring conditions with an overnight thunderstorm softening the fairways and greens, and Woods - fresh from winning his eighth WGC Bridgestone Invitational on Sunday by seven shots - scrambled par on his first two holes, the 10th and 11th.
A creek which runs across the 13th fairway around 300 yards from the tee meant Woods hit an iron off the tee, despite the par five measuring 598 yards, but after another iron left him 150 yards from the green the 37-year-old fired a superb approach to within two feet of the flag to set up his first birdie of the day.
Woods also birdied the par-three 15th, holing from 10ft, but missed a great chance on the second, his birdie attempt from three feet not even touching the hole.
A poor tee shot on the par-five fourth - the first time he had used a driver - contributed to another bogey and worse was to follow on the ninth, where he came up short of the green and then pitched into the face of a greenside bunker.
Furyk, looking to become the second 43-year-old in succession to win a major after Phil Mickelson's Open triumph, was set to equal the course record of 64 when he reached six under, but bogeyed the last for a five-under 65.
The former US Open champion led by one from Canada's David Hearn, with Casey joined on three under by American pair Robert Garrigus and Matt Kuchar and Australian Marcus Fraser.