Luke Donald and Lee Westwood have a mountain to climb after costly late slips left them six shots back going into the final day of the USPGA in Atlanta.
The English pair, still trying to validate their status as the top two in the world by winning a first major, slipped to tied 13th as unheralded Americans Brendan Steele and Jason Dufner moved to the top of a US-dominated leaderboard.
Steele, a winner in Texas earlier this year but playing in his first major, moved two clear at one stage before a bogey at the last saw him post a four-under 66 and take the clubhouse lead at seven-under.
And he was later joined on that number by Dufner, who birdied the tough 15th and 16th before making pars at the final two holes in a round of 68.
Keegan Bradley is just one back at six-under after a 69 while veterans Scott Verplank (-5) and Steve Stricker (-4) make it an all-American top five.
Both Donald and Westwood will feel they should be much closer after walking off the par 70 Highland course at Atlanta Athletic Club.
Westwood even joked about changing religions because he has tried everything else to hole more putts.
Donald, meanwhile, talked of possibly going off to “punish” himself in the gym after a closing double-bogey six sent him tumbling down the leaderboard.
“I’m completely fed up. I’ve had enough now,” said Westwood after dropping two shots on the 468-yard 14th in an otherwise bogey-free 70.
“I made two birdies and they were from five-foot putts. I missed five inside 10 feet and you can’t do that on these greens – everybody else is making them.”
Asked what more he can do to cure a problem that has dogged him most of the season, Westwood replied: “Different religion maybe. I’ve tried everything else and I need inspiration from somewhere.
“I would like to think they will drop tomorrow, but they haven’t dropped all year, so why should they tomorrow?”
The double bogey came when he drove into sand, rolled down a cart path with his second and then three-putted, missing from inside four feet just as he had for birdie on the long 12th.
Donald was seething after becoming another victim of arguably the toughest closing hole in golf.
The world number one faced a 10-foot putt on the short 15th to take a share of top spot – it would have made him a brilliant six under par for the day – but missed it and after bogeying the 16th, the 507-yard par-four 18th saw him drive into sand and then go in the water with his third shot.
“I am angry,” he said after signing for a 68 and one-under aggregate.
“I had something good going and I threw it away.
“It’s just a shame to waste it like I did. I worked so hard to get to five under.
“Those last few holes are tough, but on the third shot to 18 I was probably too aggressive with my line and just pushed it.
“I gave myself a lot of chances, that’s the positive thing, and if I can go low tomorrow who knows? But obviously the finish leaves a bitter taste in my mouth.”
The leading Europeans are now Dane Anders Hansen (70) in a tie for sixth on three under with DA Points and Swede Robert Karlsson (67), who sits at two-under alongside the 2001 winner here, David Toms, Masters champion Charl Schwartzel and Aussie duo Adam Scott and John Senden.
Rory McIlroy, meanwhile, admitted to frustration as his hopes evaporated with a four-over-par 74 and dropped outside the top 60 on seven over par.
Tee-off times in the final round of the USPGA Championship at Atlanta Athletic Club, Georgia (USA unless stated, all times local, BST is +5 hours):
Starting at hole 1
1310 Paul Casey (Eng)
1320 Sean O’Hair, Shaun Micheel
1330 Edoardo Molinari (Ita), Ryan Moore
1340 Peter Hanson (Swe), Pablo Larrazabal (Spa)
1350 YE Yang (Kor), Rickie Fowler
1400 Padraig Harrington (Irl), Michael Bradley
1410 Ross Fisher (Eng), Rory McIlroy
1420 Andres Romero (Arg), Noh Seung-yul (Kor)
1430 Davis Love, Zach Johnson
1440 Ricky Barnes, Rory Sabbatini (Rsa)
1450 Robert Garrigus, Kevin Streelman
1500 Miguel Angel Jimenez (Spa), Johan Edfors (Swe)
1510 Kyung-tae Kim (Kor), Mike Small
1520 Yuta Ikeda (Jpn), John Rollins
1530 Harrison Frazar, Charles Howell
1550 Matteo Manassero (Ita), Robert Allenby (Aus)
1600 Chris Kirk, Bryce Molder
1610 Jerry Kelly, Jhonattan Vegas (Ven)
1620 Ian Poulter (Eng), Johnson Wagner
1630 KJ Choi (Kor), Bubba Watson
1640 Simon Dyson (Eng), Mark Wilson
1650 Gary Woodland, Trevor Immelman (Rsa)
1700 Brian Davis (Eng), Kevin Na
1710 Brandt Jobe, Bill Lunde
1720 Sergio Garcia (Spa), Scott Piercy
1730 Phil Mickelson, Ryan Palmer
1740 Matt Kuchar, Bill Haas
1750 Francesco Molinari (Ita), Alexander Noren (Swe)
1800 Jim Furyk, Hunter Mahan
1810 Brendon de Jonge (Zim), Lee Westwood (Eng)
1830 Luke Donald (Eng), Spencer Levin
1840 Ben Crane, Nick Watney
1850 Adam Scott (Aus), John Senden (Aus)
1900 Charl Schwartzel (Rsa), Robert Karlsson (Swe)
1910 DA Points, David Toms
1920 Steve Stricker, Anders Hansen (Den)
1930 Keegan Bradley, Scott Verplank
1940 Brendan Steele, Jason Dufner