Open 2014: Rory McIlroy says state of mind is responsible

McIlroy will play with Dustin Johnson on Saturday

Rory McIlroy will hope to tap into his "inner peace" as he resumes his quest for a third major and first Open title at Hoylake on Saturday.

The 25-year-old leads the Open by four shots after two majestic rounds of 66 and says his serene state of mind - and booming driver - are responsible.

He said: "I'm very comfortable in this position. It's a combination of confidence and being mentally strong.

"It's just a state of mind where you think clearly."

His main challenger is American Dustin Johnson, chasing a first major title after several near-misses, but Saturday's forecast thunderstorms and heavy rain could shatter everyone's peace.

Open organisers the R&A have introduced a first-ever two-tee start from 09:00 BST in order to get the third round completed before the severe weather hits.

"If it's just raining hard and windy and generally unpleasant they will be out there playing," said the R&A's David Rickman. "But as soon as we have thunderstorms I'm afraid we are not playing golf."

McIlroy, who confessed he was a fair weather player at the 2011 Open at Royal St George's, insists he is prepared for anything.

"I feel like I'm ready for whatever conditions come because I've practised the last few weeks in links-type conditions," he said.

"I've practiced the shots I might need in windy conditions or wet conditions.

"In a way having that four-shot lead makes it tougher for the guys to catch you. But golf is a very fickle game. Hopefully I can just keep up the solid play for another couple of days."

McIlroy's command of the tournament follows a trend in this year's majors. Bubba Watson led by three at halfway before going on to clinch a second Masters, while runaway champion Martin Kaymer was six clear after 36 holes in the US Open at Pinehurst.

Twelve months ago, McIlroy confessed to feeling "brain dead" as he missed the cut in the Open at Muirfield.

But his form over two days at Royal Liverpool suggests the Wentworth PGA Championship winner is back in the zone that brought his first two majors.

McIlroy broke a host of scoring records when he cantered to the 2011 US Open by eight shots and he also set a US PGA Championship record with an eight-shot winning margin at Kiawah Island in 2012.

"If my driving is there, everything else sort of feeds off that," said McIlroy, who unleashed one of 396 yards on the 17th on Friday and is second in driving stats behind American Brooks Koepka.

But McIlroy, who blew a four-shot lead on the final day at Augusta in 2011, added: "I've been in this position at major championships before, there's still a lot of golf to play."

Johnson, 30, is, like McIlroy, another prodigious hitter who combines length with a deft short-game and hot putter.

American Johnson won the last of his eight PGA Tour wins in November 2013, and has played in the final group of a major three times without securing a win.

In the 2010 US Open he led by three going into the final day but collapsed to an 82 behind McIlroy's countryman Graeme McDowell.

At the 2010 US PGA at Whistling Straits he was penalised for grounding his club in an area of sand deemed a bunker on the 18th and missed out on a play-off by one as Kaymer won.

And he finished second behind another Northern Irishman Darren Clarke in the 2011 Open at Royal St George's.

Johnson is happy to be playing alongside McIlroy and said: "I am always excited to be in the mix.

"I had a lot of fun out there and tried to stay relaxed. I am swinging really well and felt comfortable over the golf ball. I am looking forward to it.

"I'm glad I'm in the last group and playing with Rory - but I've got to go out and play my game. I can't worry about what he is doing. I'll just go out there and try to shoot a good number."

American Rickie Fowler, one of six players who are six shots back, does not expect McIlroy to come back to the field.

He said: "When his driver is on he's almost unstoppable. I know he gets a little off here and there but I don't think he has a whole lot of weakness.

"I know there's been a couple of Fridays where he's struggled a little bit and kind of fallen back but it seems like he just gets a little off with the driver, misses a few putts and the momentum goes the other way."

Sergio Garcia, another player six shots behind, is hopeful that the conditions can still play a part.

He said: "We will see how he finishes. Obviously he is playing well. He is a wonderful player, we all know that, and he is going to be difficult to beat.

"When it plays tough like this, anything can happen."