World number one Rory McIlroy believes three days as a tourist in London turned out to be the perfect preparation for his bid to win a second US Open title.

And, despite comparing the hard and fast conditions at Chambers Bay to those for the 2013 Open, McIlroy has promised there will be no repeat of the "brain-dead" performance and missed cut he suffered at Muirfield.

"I'm a completely different player," said McIlroy. "I'm in a completely different place. I had no control of my golf game at that point in time and I feel like I'm pretty much in full control of it at the minute. I can tell you a repeat of that is definitely not going to happen."

McIlroy, who was struggling to adapt to his new clubs in 2013 following his controversial multi-million pound switch to Nike, labelled his play "brain-dead" after covering the back nine at Muirfield in 42 in his opening 79, including putting off the 15th green into a bunker.

It took until December that year for McIlroy to register his first win of the season, after five in 2012, but the 26-year-old then recorded four victories in 2014, including his third and fourth major titles in the Open Championship and US PGA.

"Chambers Bay plays more like a links course than some links courses," McIlroy added. "It's so fast, so firm. It reminds me of 2013 at Muirfield and '06 at Hoylake when Tiger (Woods) won. The course is getting burned out."

McIlroy's Open victory also came at Hoylake and he feels that will suit his game better than the likes of Irish Open venue Royal County Down, where strong winds contributed to a second successive missed cut after two wins in his previous four events.

"I felt like at Hoylake, I didn't need to adapt my game that much to how I played it in relatively benign conditions, so after playing at County Down I was just trying to get back to playing my normal game, not really trying to play these little half shots or trying to play the ball along the ground," McIlroy added.

"Even this week I was expecting to have to play the ball along the ground more. But looking at all these elevated greens you're not going to have to do that too much because the greens are so firm.

I feel with some of the elevated approach shots you need to be able to hit the ball up in the air with quite a lot of spin, which fortunately I'm able to do.

"It'll really reward people that are hitting good shots and are confident and their short games are sharp" - Rory McIlroy on the Chambers Bay course

"I obviously didn't want to miss those two cuts in Europe, but I think that's just the way I'm going to be. I'd rather in a six-tournament period have three wins and three missed cuts than six top-10s.

"Volatility in golf is actually a good thing. If your good weeks are really good, it far outweighs the bad weeks.

"I had commitments with Nike on the Monday after (the Irish Open). I did some biomechanical testing on the Tuesday. My trainer Steve (McGregor) was over on Wednesday, so we did a couple of sessions.

"And then I went to London on Thursday for a few days. I was a tourist for three days, went to the London Eye, did a lot of walking, which I didn't know was a great preparation for this place.

"I think I walked about 10 miles a day, so that helped. That got me in the right frame of mind."

McIlroy was the centre of attention as he tried to complete the career grand slam at the Masters in April, but with Phil Mickelson in that position this week after six runners-up finishes in the US Open, the Ulsterman is enjoying a quieter build-up.

"There's not as much attention or much hype," McIlroy added. "I can get here and just do my thing without much worry. And I guess there's not as much on my mind about what I can achieve.

"It's hugely important, a chance to win a second US Open and the fifth major, and that's all important, but there was just so much hype and so much attention around Augusta.

"This one feels very different."

Conditions certainly are different to the long, wet course at Congressional when McIlroy won his first major title by eight shots in 2011.

But the Ryder Cup star believes a similarly large winning margin could be on the cards given the tough test posed by Chambers Bay.

"I think a place like this can separate the field a lot," he added.

"This is the sort of golf course that if you're just slightly off, it'll magnify that. But it'll really reward people that are hitting good shots and are confident and their short games are sharp.

"The guys that are really playing well and are confident with the set-up and how they approach it, they could really separate themselves from the rest of the field."