Marc Leishman has had a dramatic stumble to fall back from the lead midway through the third round at the US Open.
Leading the Australian tilt at Shinnecock Hills, Leishman was climbing up the leaderboard at one-under-par through seven holes before a triple-bogey at the par-4 eighth.
World No.14 Leishman had 22 feet left on the green for par but four-putted for a score of seven.
Starting the back nine on moving day with two bogeys, the three-time winner on the US PGA Tour now sits at seven over and seven shots back of the lead.
Overnight leader Dustin Johnson is also struggling. The world No.1 dropped five shots to fall to one over, opening the door for former British Open winner Henrik Stenson to take the lead at even par.
Johnson shares second place with defending champion Brooks Koepka and 2013 US Open winner Justin Rose.
Rounding out the Australian contingent is four-time US Tour winner Aaron Baddeley, who had a day to forget with a 77 sinking him to 13 over.
Earlier, five-time major winner Phil Mickelson caused US Open controversy by striking a moving golf ball during a bizarre meltdown.
Mickelson chased after his travelling ball on the 13th green on day three and struck it before it could roll further from the hole, breaching rule 14.5 which prohibits a player from hitting a moving ball.
The 48-year-old, who has a record six runner-up finishes at the US Open, was assessed a two-stroke penalty by organiser the USGA and given a 10 for the hole.
He signed for an 11-over-par 81 and a 17-over total.
Mickelson tried to downplay the controversy and offered a feeble apology to reporters after signing his scorecard.
"If someone is offended I apologise but toughen up," Mickelson said.