Rory McIlroy’s not doing simple at the moment. Less than a week on from his victory at the BMW PGA Championship at Wentworth - his first PGA Tour win since 2012 - and less than two weeks since his sudden break up from fiancée Caroline Wozniacki, McIlroy is continuing his recent trend of peaks and troughs.

The Northern Irishman’s on course form plummeted as he endured a day of dramatic failure at the Memorial Tournament. Following on from a scintillating 63 on Thursday, McIlroy allowed a three shot lead evaporate with a miserable 78 that included three double bogeys in his opening 6 holes. Starting on the back 9, the former world number 1 completed those 9 holes in 12 shots more than he had on Thursday. A pair of birdies on the front 9 offered some consolation, though at 9 shots off the lead it appears unlikely to be more than that.

England’s Paul Casey seized on McIlroy’s double bogey streak to move 3 shots ahead of the pack, scoring a second 66 in as many days. Casey’s round was highlighted with an eagle and peppered with birdies- six in all. Two dropped shots left his total for the tournament at 12 under.

Masters champions Bubba Watson is in second, 3 shots back following a 69. American Chris Kirk is a shot further back, with a 70 on Friday.