Golf:Rory McIlroy saw his hopes of winning the Korea Open bite the dust on the back on a two-over-par 73 in the third round as Rickie Fowler took a four-shot lead as he attempts to record his first victory as a professional.

US Open champion McIlroy had started the third round in a five-way tie for top spot, with Fowler also on five under.

Birdies on the sixth and eight holes helped McIlroy get to seven under, but he would drop his first shot of the day at the eight.

Fowler, playing in the group ahead, picked up five birdies in the first eight holes to move to 10 under and his lead over McIlroy would increase on the back nine with three further gains in a stunning course record of eight-under 63 that left him on 13 under with 18 holes to play.

In contrast, McIlroy has a horror back nine, with three bogeys and a double bogey in the space of five holes. He dug deep, though, claiming birdies on the two closing holes to sign for a two-over 73 and drop back to a tie for fourth spot alongside Australia’s Bronson La’Cassie.

Fowler is four clear of defending champion YE Yang, who overcame a 10-shot deficit last year to claim his second national title. Korean teenager Kim Meen-Whee is two shots further back.

“I had a good round and I can’t complain with a 63,” said 22-year-old Fowler. “Going into the round I wanted to drive the ball well and make some putts, and I was able to do that and that puts me in a good position. My goals were to drive well and putt well, but my overall game was also good.

“I think I can win,” he added. “I feel good about my game and I’m in a great position, which is right where I wanted to be coming into the week.”

McIlroy highlighted a short missed putt on the ninth and a mix-up with a rules official on the back nine in explaining his bad day at the office.

“I had a good finish, but it was not my best day. I played quite nicely over the first few holes, but the pin positions were very tricky. I was two under through eight holes and I felt pretty good, but I missed a little putt on nine which threw me a little,” said McIlroy.

“I played 10 and 11 pretty well, but I hit a tee shot on 12 which I have not hit that wide all week. And after I hit my first ball out of bounds, I then hit my second in the rough and as I was taking a practice swing I hit another ball which I didn’t see and at first the rules official said that I had played a wrong ball.

“I had no intention of hitting it, but I got it up and down with the other ball and thought I had made seven, but the rules official then said it was okay and I actually made five. That got into my head a little and I lost it a bit on the back nine and I got on a bit of a bad run, but I then played the final two holes a lot better after two good drives.”