Goosen - stunning finish to third round. (Getty Images)

Retief Goosen, as quiet and unassuming a superstar as there has ever been, is poised to become US Open champion for the third time in five years.

On a Pinehurst course where he shot 75 and 82 six years ago and missed the cut, the South African takes a three-stroke lead into the final round after a real rollercoaster ride of everything except his emotions.

They always stay the same - cool, calm and collected. Completely unflappable, it appears on the surface at least.

The defending champion, looking to join Ben Hogan and Curtis Strange as the only back-to-back winners of the title since the Second World War, had a two-hole wobble early in the back nine of his third round when he went bogey, double bogey.

But his response was to birdie the next two holes, the 14th and 15th, and then at the 442-yard last he holed from off the green for a joint best-of-the-day 69.

Goosen, trying also to be just the sixth player to have a hat-trick of victories in the event, is the only man under par. He is on the three-under mark of 207, with his nearest challengers Olin Browne and Jason Gore - the two Americans with whom he shared the halfway lead - level par.

The 36-year-old's dazzling finish could well have left all but a few with too much catching up to do - including Lee Westwood, who in contrast bogeyed two of the last three for a 73 to drop six behind along with Tiger Woods.

Westwood, bidding to end a 35-year wait for a European winner of the title, will not give up the chase, of course.

"I think level par or one over could have a very good chance," he said. But that was before Goosen delivered his last thrust from 25 feet.

Thanks to a chip-in at the 11th and a 30-foot putt on the next, Westwood was right on the heels of the leaders, but on the 18th he had to make an eight-footer just to drop one shot after tangling with sand and while it felt good not to double bogey the task looks a tall one now.

He is not the only European in seventh place. Swede Peter Hedblom, who qualified two weeks ago at Walton Heath with an eagle and three birdies in his last four holes, followed up his course record 66 with a 70 and will be the one partnering Woods on the final day.

But Sergio Garcia and Luke Donald fell eight and nine adrift after scoring 75 and 74 respectively.

Gore, 818th in the world and not even a member of the US tour at present, matched Goosen's outward 35, but then bogeyed the 11th and double-bogeyed the 14th.

To the 31-year-old's credit, though, he parred the next three and also birdied the last for a 72.

Browne, himself 300th in the rankings, also finished strongly. Two over with four to go he birdied the 15th and 17th to push New Zealand's Michael Campbell and Australian Mark Hensby into joint fourth spot on one over.

Westwood has been a member of three victorious Ryder Cup sides, has lifted titles all around the globe and been as high as fourth in the world.

But he has yet to have a top-three finish in a major and as he attempted to change that he received a good luck message from close friend Darren Clarke.

The Ulsterman, of course, is not playing this week because his wife Heather is battling cancer, but the good news is that she hopes to be back home on Tuesday and Clarke is planning to make his return in the European Open in Dublin in two weeks' time.

Earlier, helped by a hole-in-one, American Peter Jacobsen kept alive the chance of becoming the oldest-ever winner of a major title.

The 51-year-old former Ryder Cup player, who earned a spot in the field by capturing last year's US Seniors Open, aced the 175-yard ninth hole en route to a sparkling 69.

"As it left the club it was right on line. At first I thought it might have hit the flag and gone over, but the fans then raised their arms like 'touchdown'," said Jacobsen, who had a part in the film "Tin Cup" starring Kevin Costner as a struggling pro trying to win the US Open.

"If I said I thought I could win coming in here I would be lying, but I thought I could make the cut."

Jacobsen was on the four-over total of 214 as predictions of an over par winning score in the event for the first time since 1978 were starting to look spot on.

Nine players were under par after the first round, five at halfway and that has now come down to one.

World number one Woods cannot be ruled out just yet. After bogeys at two of his first three holes he parred the next seven, then birdied the 11th before three-putting the next and parring his way in.

Woods had escaped disqualification, but had come in for stinging criticism from fans and commentators for his scraping of the ninth green with his putter in annoyance at missing a putt in the second round.

Officials decided it did not constitute a serious breach of etiquette because it was a one-off and he did make a small attempt to repair the damage, but his behaviour was being monitored and tossing his club after missing the green at the first on Saturday did not help.

Vijay Singh is seven behind after a 74 after double-bogeying the driveable third. He chose to lay up, then pitched over the green and three-putted.

Phil Mickelson and Ernie Els looked out of the running at eight over and nine over following rounds of 72.

Bizarrely, Mickelson birdied the toughest hole, the 16th, but triple-bogeyed the easiest - the long fourth. He went out of bounds with his drive there.

Els was one under going out, but four-putted the 10th for a double-bogey seven and needed three attempts to get onto the raised green at the 13th to drop two more shots.

"Anybody within probably five shots (after the round) has a realistic shot," commented Mickelson. He had to wait to see if that included him and when Goosen did as he did Mickelson presumably ruled himself out.

In fact, on that basis it is down to six - Goosen, Gore, Browne, Campbell, Hensby and David Toms on two over. With Goosen the red-hot favourite.

Collated third-round totals (US unless stated):

210 Jason Gore 71 67 72, Olin Browne 67 71 72

211 Michael Campbell (Nzl) 71 69 71, Mark Hensby (Aus) 71 68 72

212 David Toms 70 72 70

213 Peter Hedblom (Swe) 77 66 70, Tiger Woods 70 71 72, Lee Westwood 68 72 73, KJ Choi (Kor) 69 70 74

214 Peter Jacobsen 72 73 69, Arron Oberholser 76 67 71, Steve Allen (Aus) 72 69 73, Vijay Singh (Fij) 70 70 74

215 Tim Clark (Rsa) 76 69 70, Corey Pavin 73 72 70, Nick Price (Zim) 72 71 72, Adam Scott (Aus) 70 71 74, Sergio Garcia (Spa) 71 69 75

216 Kenny Perry 75 70 71, Paul Claxton 72 72 72, Luke Donald (Gbr) 69 73 74, Keiichiro Fukabori (Jpn) 74 67 75, Jim Furyk 71 70 75

217 John Cook 71 76 70, Justin Leonard 76 71 70, Davis Love 77 70 70, Tim Herron 74 73 70, Geoff Ogilvy (Aus) 72 74 71, Shigeki Maruyama (Jpn) 71 74 72, Ted Purdy 73 71 73, Angel Cabrera (Arg) 71 73 73, Steve Jones 69 74 74

218 Bernhard Langer (Ger) 74 73 71, Bill Glasson 74 73 71, Phil Mickelson 69 77 72, Ryuji Imada (Jpn) 77 68 73, Charles Howell 77 68 73, Bob Estes 70 73 75

219 Paul McGinley (Irl) 76 72 71, Ernie Els (Rsa) 71 76 72, Colin Montgomerie (Gbr) 72 75 72, John Mallinger 74 72 73, Rob Rashell 74 72 73, Peter Lonard (Aus) 71 74 74, Fred Couples 71 74 74

220 Graeme McDowell (Gbr) 74 74 72, Chad Campbell 77 71 72, Tom Pernice 74 73 73, Stewart Cink 73 74 73, Ian Poulter (Gbr) 77 69 74, Nick Dougherty (Gbr) 72 74 74, Thomas Bjorn (Den) 71 74 75, Fred Funk 73 71 76, Brandt Jobe 68 73 79

221 (x) Matt Every 75 73 73, Thomas Levet (Fra) 75 73 73, Jonathan Lomas (Gbr) 72 74 75, Nick O'Hern (Aus) 72 71 78, Steve Flesch 72 71 78, tommy Armour 70 72 79

222 JP Hayes 77 71 74, Lee Janzen 74 74 74, DJ Brigman 74 73 75, Jeff Maggert 72 75 75, Mike Weir (Can) 75 72 75, JJ Henry 73 73 76, Rory Sabbatini (Rsa) 72 74 76, Stephen Ames (Can) 71 75 76, Michael Allen 73 72 77, Soren Kjeldsen (Den) 74 71 77, Richard Green (Aus) 72 72 78, Steve Elkington (Aus) 74 69 79

223 Omar Uresti 75 73 75, (x) Ryan Moore 75 73 75, Craig Barlow 76 71 76, John Daly 74 72 77

224 JL Lewis 75 73 76

225 Jerry Kelly 76 71 78, Bob Tway 71 75 79

226 Frank Lickliter 75 73 78, Chris Nallen 76 72 78