Ryder Cup hero Martin Kaymer evoked memories of Rory McIlroy's runaway victory in 2011 as he continued his remarkable domination of the 114th US Open Championship.
Kaymer said after his opening 65 - the lowest score ever in the US Open at Pinehurst No.2 - that no-one should expect him to do it again, but that was precisely what he did on Friday to set another record.
The 29 year old's halfway total of 130 eclipsed the previous championship best of 131 set by McIlroy at Congressional, although the Northern Irishman was 11 under and Kaymer 'only' 10 under after 11 birdies and just one bogey over the first two days.
McIlroy's halfway lead of six shots three years ago equalled the record set by Tiger Woods at Pebble Beach in 2000 - Kaymer was eight ahead of Zimbabwe's Brendon de Jonge and American trio Keegan Bradley, Dustin Johnson and Brooks Koepka as the afternoon starters headed onto the course.
"It's not a done deal," insisted Kaymer, who joined McIlroy as the only players to get to double digits under par in the first two rounds. "You don't approach Saturday and Sunday in a relaxed way.
"It's never a time when you can relax, unless it's Sunday afternoon and you are raising the trophy. There's never a time you can take it easy, you have to set your own goals and keep playing well."
Looking to become the first person to win The Players Championship and US Open in the same year, Kaymer played down concerns over the strapping on his left wrist, adding: "It's just (down to) a lot of practice and golf the last few months but it's no problem, I'm feeling good.
"I played very solid again, did not make a bogey which was nice. I struggled a bit the last few holes but kept it together well."
Kaymer had covered the back nine in 31 on Thursday and quickly demonstrated his liking for it on Friday, making light of the 627 yard par five tenth - his opening hole - by holing from six feet for birdie.
The former World Number One missed from 12 feet for birdie on the 12th but quickly made amends, holing from twice the distance on the next.
Asked on Wednesday what score he would be happy with after four rounds, Kaymer had said eight over par. Another birdie from 25 feet on the 16th took him to eight under after just 25 holes.
The tee on the par four third had been moved forward to bring the green into range and Kaymer took full advantage, driving the green from 315 yards and two-putting for his fourth birdie of the day.
Another soon followed on the fifth and despite a number of mishit iron shots on the closing stretch, Kaymer kept a bogey off his card to leave the chasing pack facing a monumental task to deny him a second Major title.
His first came in the US PGA Championship at Whistling Straits in 2010, when Johnson was famously denied a place in the play-off between Kaymer and Bubba Watson due to a two shot penalty on the 72nd hole, the 29 year old grounding his club in a bunker that he thought was a waste area.
Speaking after carding his second consecutive 69, Johnson said: "I would have taken it on Wednesday. And no, I wouldn't have thought it would be eight shots behind."
Koepka, who won three times on The Challenge Tour last year to secure automatic promotion to The European Tour, said: "Martin seems to be playing a different golf course, ten under is incredible.
"But if I just take care of myself I should be fine come Sunday. You never know what can happen. One shot out here, one bad shot could cost you two, maybe three. So you are never too far out of it, I don't think, especially in a US Open."
World Number One Adam Scott, who carded a second round of 67 - the lowest score of the week without Kaymer - to get back to level for the tournament, added: "It's great golf from Martin.
"There are so many talented guys and he's certainly one of them and he's confident enough after winning a big event already this year. For him to come out today and back it up is super. If he does it for two more days, then we're all playing for second spot.
"But we all know that US Opens get very difficult and if I can just somehow put together two really good rounds, maybe slowly but surely I'll creep my way up towards Martin."
