Australian Jason Day will take a two-shot lead into the final round of the PGA Championship at Whistling Straits.
Day carded a third-round 66 to move to 15-under for the tournament, two clear of Jordan Spieth. Justin Rose and Branden Grace are next best on 12-under, with 2010 PGA Championship winner Martin Kaymer a further shot back.
World number one Rory McIlroy carded a third-round 68 to move to six-under.
Day opened his round in up and down fashion, with three birdies and two bogeys in the opening five holes. It was around the turn that the Australian made his move, as he birdied the ninth and 10th holes before notching up an eagle-three at the par-five 11th and further birdies at the 13th and 14th.
The Queensland native would then stutter slightly, with a double bogey at the 15th after a miss-hit chip from s bunker seeing his lead cut by two. A poor chip from the edge of the green at the 16th resulted in a par when a birdie had seemed a certainty, and for a moment it seemed that Day may come unstuck.
However, he responded in the best possible way, with a great birdie-two at the 17th before narrowly missing out on the chance to extend his lead to three at the last.
Day will be joined in Sunday's final pairing by Spieth who produced a top quality seven-under par 65 to move to 13-under for the tournament.
Spieth opened with a birdie at the first before reeling off eight pars to take the turn in 35. The world number two kicked on over the back nine, notching up six birdies in the last six holes to hurtle up the leaderboard to 13-under.
While the putts weren't dropping for Spieth over the front nine, the Texan continued to give himself opportunities, and on the closing nine he started to find his range with the putter and the result was slew of birdies that demonstrated Spieth's class.
The 22-year-old is now 50-under for the year's four majors, an incredible run that sees him on the verge of a magical third major of the year.
One shot further back are Grace and Rose who fired rounds of 64 and 68 respectively.
Having begun the day on seven-under, three shots off the pace, Rose made the perfect start, sinking a 40-foot birdie putt at the first. However, for the second day in succession, the Englishman slumped to a double-bogey six at the fourth after driving into a fairway bunker and then three-putting from 30 feet.
He was soon heading in the right direction once more though, having taken off his shoes to play out from near the water, Rose holed a 20-foot putt for an unlikely birdie at the fifth, with further birdies following at the seventh, ninth and 11th.
Rose picked up further shots at the 14th and 16th, before ending with a disappointing bogey at the 18th after his approach landed in the rough just short of the green.
Grace, who had begun the day seven strokes off the pace, notched up a bogey-free round of 64 that included eight birdies. The highlight of the day for the South African was a super chip-in at the last from trouble below the green.
Kaymer had played his third round alongside Grace, and they appeared to spur each other on, with the German enjoying a fine round of 65 which consisted of two birdies on the opening nine and a further five on the back nine as the former world number one went without a bogey on the day.
Overnight leader Jones, making just his eighth appearance at a major, coped well with the pressure early on, registering birdies at the first and sixth, before a bogey at the ninth after a hooked drive into the hospitality area saw him take the turn in 35.
However, it all went array for Jones in the final hour, with the Australian slumping to back-to-back bogeys at 15 and 16 before a double-bogey five at the par-three 17th after he hooked his drive to the left saw him stutter to a 73.
Jones is joined on 10-under by Tony Finau who continued to impress in just his second major with a 69 after a late wobble saw him drop back slightly.
India's Anirban Lahiri and Dustin Johnson are a further shot back on nine-under after carding rounds of 70 and 68 respectively.
McIlroy, who had begun the day nine shots off the pace, shot up the leaderboard early on, with birdies at the second and fourth holes before holing a 65-foot eagle putt at the fifth.
However, bogeys at the sixth and eighth after finding the sand on multiple occasions saw him take the turn in 34, before four birdies and four bogeys on the back nine resulted in a round of 68 that took the Ulsterman to six-under.