World No.1 Tiger Woods struggled to a third round of 73 at Oak Hill to finish four over par, 13 shots behind Jason Dufner just as the halfway leader headed to the first tee.
And Open champion Phil Mickelson fared considerably worse with a 78 that equalled his highest score ever in the US PGA and left the 43-year-old 10 over par, 74th of the 75 players who made the cut.
Woods had come into the final major of the year fresh from shooting a second-round 61 en route to winning an eighth Bridgestone Invitational by seven shots on Sunday, his fifth victory this season.
But, barring something truly miraculous, the 14-time major winner will leave Rochester today no closer to equalling Jack Nicklaus’ record of 18.
Instead he will have gone 18 without a win stretching back to his last triumph in the 2008 US Open.
Woods began the day ten shots behind Dufner and needing to create history to claim an unlikely win, the biggest comeback by a US PGA winner after 36 holes being nine shots by Bob Rosburg in 1959 and Bob Tway in 1986.
However, the 37-year-old found heavy rough from the first tee and from there hooked his second shot into a tree some 50 yards in front of him. He was lucky to see the ball bounce back into the fairway, but then played a poor pitch to 15ft and left his par putt well short of the hole.
Woods also bogeyed the third after missing the green and failing to get up and down, but at least saved par after bad drives on the fourth and ninth and birdied the 11th – only his seventh birdie of the week.
Two more bogeys followed on the 16th and 17th and left Woods facing up to a fifth straight year without a major. Mickelson at least has the consolation of winning the Open last month, but the left-hander looked a different player to the one who shot a superb closing 66 at Muirfield.
The 43-year-old began with good birdie chances at the first and second and made one from four feet on the third, but then three-putted the par-five fourth.
Worse was to come on the seventh as one of the best short-game players in the world duffed two chips a total of six feet to run up a triple-bogey seven, while another dropped shot on the ninth took Mickelson, pictured left, out in 39 – ten shots more than Justin Rose needed to cover the same stretch yesterday.
Mickelson’s misery continued with a double bogey on the short par-four 14th, when he twice pitched from one side of the green off the other, and he also bogeyed the 15th - after hitting his tee shot into the water - 17th and 18th.
In contrast, his Ryder Cup team-mate Dustin Johnson had shown what was still possible with a 65 after making the cut right on the mark of three over.
Johnson carded two birdies and one bogey in a front nine of 34 before picking up shots on the 10th, 13th, 14th and 15th to move into the top 20 on two under par.
Asked to sum up his week, Woods said: “Not joyous, that’s for sure. It’s just one of those weeks where I didn’t quite hit it well enough and didn’t make enough putts. That’s golf. We don’t play well every week.”
He denied he was trying too hard in majors, adding: “As far as that’s concerned, no. As far as overall game plan and the way I’m playing, I’ve been there in enough of these things where I’ve been right there in the back nine on Sunday with a chance.”
Back on the course, Dufner opened with three straight pars and that was enough to extend his lead to three shots as Scott and Kuchar both birdied the first before falling back.
Scott dropped shots at the second and third while Kuchar duffed a chip to double-bogey the third, the same hole also costing Justin Rose two shots after he missed the green by 50 yards and then three-putted.
Rose had also bogeyed the second and from three behind had fallen six off the pace in his bid to join golfing legends Gene Sarazen (1922), Ben Hogan (1948), Jack Nicklaus (1980) and Tiger Woods (2000) as the only men to have won the US Open and US PGA in the same year.