World Number One Dustin Johnson fired a seven over par 77 but still held a share of the lead heading into the final day of the US Open after Shinnecock Hills Golf Club pushed the world's best right to their limits in an intense and dramatic third round.
The American started the day with a four-shot lead at four under but in windy conditions and on lightning fast greens with tough pin positions in the afternoon, he slipped to three over and into a four-way tie with defending champion Brooks Koepka and two more Americans in Daniel Berger and Tony Finau.
Berger and Finau started the day 11 shots off the lead and were still seven behind when Johnson teed off despite equalling the lowest rounds of the week with a pair of 66s.
At the end a remarkable day when everyone in the final 22 groups moved backwards, they were in the final group on Sunday, with Koepka set to play alongside Johnson after a 72.
Englishman Justin Rose was a shot off the lead after a 73, one clear of Swede Henrik Stenson and two ahead of Thai Kiradech Aphibarnrat, Masters Tournament champion Patrick Reed and US Ryder Cup Captain Jim Furyk.
Berger, Finau and Aphibarnrat were the only players under par on the day after making the most of the early conditions, with the drier greens in the afternoon making putting treacherous for the leaders.
Rose and Stenson led the European Tour charge and they both held the lead at points on Saturday as they go in search of their second Major Championships.
Johnson reclaimed top spot in the Official World Golf Ranking with a win on the US PGA Tour last week and will not only be going for back-to-back wins on Sunday but also his second Major after winning this event in 2016.
“I'm in a good position in the lead tomorrow,” he said. “Today's round, I didn't feel like I played badly at all. Seven over usually is a terrible score but with the greens the way they got this afternoon, they were very, very difficult.”
I won this thing last year. I feel like you've got to kind of take it from me, to be honest with you - Brooks Koepka
A successful defence for Koepka would bring him a second victory in one of golf's four biggest events, while Finau and Berger are still searching for their maiden Majors.
Berger was the first man to set the target, turning in 32 with birdies on the second, fourth and sixth. He made further gains on the 12th, 13th and 15th but they were sandwiched by bogeys on the 11th and 17th.
“This is why I practice and play because I want to be in this position to have a chance to win golf tournaments,” he said. “It hasn't necessarily gone my way this year but I've done a lot of the right things and it's more about just letting it happen and not putting too much pressure on myself.”
Finau dropped shots on the second and third but bounced back on the fourth and fifth and came home in 31 with gains on the tenth, 11th, 12th and last.
“If I can feed off the energy I had late in today's round and continue that momentum into tomorrow, it will be fun,” he said. “I was able to bounce back and I think more mentally I allowed myself to do that, more so than physically. I feel like I have the capability to play well out here.”
Koepka bogeyed the first but holed a 30-footer with a huge right-to-left break on the second to get back to one over, and when he broke a run of eight pars with a tee-shot to four feet on the 11th, he was in the lead.
That was because Johnson turned in 41, three-putting the second and seventh, coming up short with his second shots into the fourth and eighth and missing the green on the sixth.
Koepka bogeyed the 12th and an excellent Johnson tee-shot into the 11th had him back in a share at one over, but the 33 year old played a poor tee-shot on the 15th and three-putted the last, while Koepka found sand on the 15th and three-putted the 17th.
I'm in a good position in the lead tomorrow. Today's round, I didn't feel like I played badly at all - Dustin Johnson
“I feel really good about the position I'm in,” said Koepka. “There's nobody more confident, I won this thing last year. I feel really good, my game's in a good spot. I feel like you've got to kind of take it from me, to be honest with you.”
Rose holed a fairway wood from just of the third green for a birdie and while Johnson's slide put him in a share of top spot, he bogeyed the eighth, ninth and tenth. An excellent approach into the 15th brought another gain but he dropped further shots on the 16th and last.
A nice pitch on the par five fifth and a front nine of 34 meant Stenson held the solo lead at one point but he came home in 40 with bogeys on the tenth, 13th, 14th, 15th and last.
Aphibarnrat recovered from a bogey on the third with birdies on the fourth, fifth, eighth and 12th but dropped shots on the 13th and 14th before birdieing the 17th.
Branden Grace, Ian Poulter and Tyrrell Hatton were in the group at seven over, a shot clear of Matthew Fitzpatrick.