McIlroy, who was joint overnight leader with Swede Robert Karlsson, overcame a shaky start with three birdies before his rules blunder on the ninth. Had he not brushed sand away from his line on that hole, the US Open Champion would have been alongside Olesen at the top of the leaderboard.

"I wasn't thinking clearly and just made a very stupid mental mistake," explained McIlroy. "Luke said 'Don't think you can do that' and I was like 'Oh yeah, I can't, can I?'"

After his level-par round of 72, McIlroy is now on five-under, sharing fourth with a group of seven players including Tiger Woods, who shot a three-under-par 69, England's Robert Rock, who shot a two-under-par 70, and Scotland's Paul Lawrie, who also finished his round on three-under-par 69.

Meanwhile, world number 171 Olesen carded a brilliant five-under-par 67 to move to seven-under and take the lead. Northern Ireland's Gareth Maybin and Italian Matteo Mannasero are a shot back on six-under after scoring two-under-par 70 and a flawless round of seven-under-par 65 respectively.