Lucas Herbert's 'wonder shot' at Royal Birkdale as Sam Burns leads British Open

Lucas Herbert has pulled off a late-evening wonder shot at Royal Birkdale to keep his British Open hopes flickering as American Sam Burns swept into pole position to lift the Claret Jug.

Australian Herbert, who had held an overnight two-shot lead after he had equalled the lowest round ever recorded at a men's major championship with his 62, was still setting the pace halfway through his third round on Sunday morning AEST.

But it all began falling apart in the run-in after Herbert had bogeyed two in a row at 15 and 16, and looked sure to drop another at the par-five 17th after he drove into thick rough, had to take a penalty drop and was left with a mercilessly tough blind shot to the green from a wispy lie on a dune from 223 metres.

He took a giant rip at the ball and, amazingly, it ended up finishing just 6 metres from the pin.

"I think that's the best shot I've ever hit," Herbert said.

Herbert ended up parring the hole, and though he hit another poor drive at the last and had to fire out of the rough to scrabble another battling par, the 30-year-old scraped together a one-over par 71 that leaves him joint-fourth alongside American Ryan Gerard on seven under, three behind the soaring Burns.

Burns shot a five-under 65 to lead by two shots from Korean Si Woo Kim and the man of the day, New Zealander Ryan Fox, who shot the third record-equalling 62 of the week following the landmark efforts of Herbert and Burns on Saturday.

Fox had started the day in 52nd position but the son of New Zealand All Blacks' great Grant Fox ended up converting nine birdies to share the lead held overnight by Herbert, some hour-and-a-half before the Aussie even teed off.

Burns thrived alongside Bryson DeChambeau, who was cheered by his army of fans following his two-stroke penalty over a rules breach and showed considerable battling spirit as he crafted a 69 to reach six-under, still very much in the hunt.

It looks like a wide open Open on the final day, with the top 20 all within six shots of each other. Among them is not just Herbert but his rather more unlikely Victorian pal Cameron John, who shot a 69 to finish on four under, tied for 11th alongside a host of luminaries.

They include world number one Scottie Scheffler (70), who had more putting gremlins, Spanish superstar Jon Rahm (70) and former champion Xander Schauffele (66). One shot better off at five under, despite cursing a disappointing finish, is local hero Tommy Fleetwood (69).