The Open 2014 leaderboard: Sergio Garcia emerges to threaten Rory McIlroy lead

Northern Irishman is bidding to win his third major

Rory McIlroy watches his shot from the 1st tee today (GETTY IMAGES)

Northern Ireland's Rory McIlroy stressed he could not under-estimate his rivals despite heading into the final round of the Open Championship with a six-shot lead - and he was proved right.

The 25-year-old, bidding to secure the third leg of a career grand slam having already won the US Open and US PGA, insisted after his third round he would not be complacent.

McIlroy recalled how he won the BMW PGA Championship in May from seven shots back so would not rule anything out despite already virtually being crowned champion by many.

His position come under a serious challenge from Sergio Garcia as the Spaniard and his Ryder Cup Cup team-mate went head-to-head at the top of the leaderboard.

McIlroy saw his advantage cut to two when Garcia, in the penultimate group, eagled the 10th after a brilliant approach to 12 feet.

The Northern Irishman responded with a birdie at the same hole to get to 17 under and restore his cushion after back-to-back bogeys at the fifth and sixth had given the chasing pack a glimmer of hope he could be caught before a 15ft birdie putt at the ninth regained some stability to his round.

Ironically, on Saturday it was Garcia - playing in his 64th major and still desperately searching for his first victory - who had virtually conceded the title to McIlroy by admitting he was playing far better than anyone else.

American Rickie Fowler, who began the day in second place, was five off the lead as birdies at the second and 10th were not enough to keep pace.

Ireland's Shane Lowry, who came through final qualifying to book his spot at Royal Liverpool, carded a joint-best of the week 65 to post 10 under.

mfl