HOYLAKE, England (AP) -- Rory McIlroy calls it his ''second-round thing.''
Just something in his head.
Unfortunately for the two-time major champion, it's become a very real problem.
For some reason, McIlroy has struggled mightily on Fridays, a subject that came up again as he prepared for the British Open.
This year, McIlroy has played the opening round at a cumulative 49-under par. On the weekends, he's a combined 39 under. But on Fridays, for some reason, he's at 15 over.
''I have no problem shooting a low one on Thursday,'' he said. ''There should be no reason I have any problem shooting a low one on Friday.''
If only it was that easy.
Three times this year, McIlroy has opened a tournament with a 63. Not once did he build on those impressive starts to actually win the tournament. Most notably, he blew up to a 78 in the second round of the Memorial.
Last week, more of the same at the Scottish Open. McIlroy opened with a 7-under 64, only to shoot 14 strokes higher the following day. Fierce winds contributed to the dismal score, but that didn't fully explain why he had another poor showing in Round 2.
''I just got it into my head,'' McIlroy said. ''I may be putting too much pressure on myself, going out on Fridays and trying to back up a (good) score.''
At age 25, McIlroy already has two of golf's biggest titles on his resume, capturing the 2011 U.S. Open and the 2012 U.S. PGA Championship with runaway victories. He'd love to move another step closer to a career Grand Slam at Royal Liverpool, though he's never been an especially big fan of links golf.
''I guess when you go on tour and especially when you play the majority of your golf in the U.S., you start to neglect some of the shots you might need in conditions like this,'' McIlroy said. ''I don't think I've evolved that much as a links player, but I've been trying, especially the past few weeks, to play some shots, really practice hard on some of the shots that I might need this week.''
He will be playing his seventh British Open, with only one previous top-10 performance. Last year at Muirfield, McIlroy opened with a 79 and missed the cut.
''The Open Championship is a tournament that's very important to me,'' he insisted. ''And my record in it hasn't been as good as I'd like. I'd love to improve on that.''
McIlroy has gone through some big changes off the course - most notably, breaking up in May with his longtime girlfriend, Danish tennis player Caroline Wozniacki, just as they were sending out invitations for their planned wedding.
These days, McIlroy seems mainly focused on his golf, though he hardly sounded persuasive when someone asked Tuesday if he was in a better place personally than he was a few months ago.
''I'm happy with everything that's going on.''
Then, he talked about nothing but his playing schedule.
''I've got this week and then go back over to the States and the World Golf Championship and then the PGA and all the FedEx Cup playoffs and the Ryder Cup,'' he said. ''So there's a lot to keep me busy and just looking forward to that stretch of golf coming up.
''So, yeah,'' he said, sounding a bit hesitant, ''I'm happy.''
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