With caddie Steve Williams back on his bag and a roaring finish to the US Open, Adam Scott is upbeat about his prospects for the second half of the year.

The Australian threw the cat amongst the pigeons on Sunday by shooting the equal second-lowest final round score in US Open history that left him just two shots short of an unlikely playoff with Jordan Spieth.

The former world No.1 scorched the difficult Chambers Bay course with a flawless six-under-par 64, moving him to three-under for the championship.

He was the clubhouse leader for some time before Louis Oosthuizen sneaked past him, eventual winner Spieth finished two shots better and Dustin Johnson’s three-putt on the 18th meant he too fell just short of his fellow American.

Scott’s tie for fourth represented his best ever US Open finish and sends him towards the British Open in St Andrews next month full of confidence.

The 64 sits behind only Johnny Miller’s 63 (eight-under) at Oakmont in 1973 which carried the American to victory.

Peter Jacobson, (seven-under) in 1988 at The Country Club, and Tom Kite and Vijay Singh, (six-under) at Southern Hills in 2001, have also posted final round 64s in the championship.

Scott knocked in three birdies on each side of the course, with two birdies in his last three, to send a scare through those behind him.

“I feel like I had nothing to lose today and everything to gain.

“I knew I was playing well and I just couldn’t quite put it all together the first three days. I really wanted to today, Scott said.

“To be honest, it’s the kind of round I needed to get things going for me this year, hopefully.

“The course was set up quite short. I played really well and I took advantage of some of the holes playing a bit shorter and didn’t have any disasters and hit a few good shots and took advantage of them.”

Scott’s return to form coincided with caddie Steve Williams’ return on his bag.

The most consistent duo over the last four-and-a-half years in major championships, Scott admitted it was good the have the old team back together.

“We make a good team and we’ve had some success together in big events and it was great to get that back again today,” he said.

We had fun out there and I hope that continues for the remainder of the season.”