DUBLIN, Ohio (AP) -- If this keeps up, Rory McIlroy's golf game may just push his personal life out of the headlines.
After winning on the European Tour last week, McIlroy overcame a tweaked knee and a double-bogey to shoot a record 9-under 63 for a three-shot lead after Thursday's opening round of the Memorial Tournament.
''I was expecting this to happen. I've been playing well. I've been posting good numbers, good rounds. And I knew my game was close,'' he said after breaking the first-round scoring record at Jack Nicklaus' signature tournament. ''Honestly, I don't think it's got anything to do with what's happening off the golf course. It's just I've been trending in the right direction, and it's starting to all come together.''
McIlroy, of course, announced last week the end of his engagement to tennis star Caroline Wozniacki. The two had shared a high-profile relationship on social media. When their wedding plans fell apart and they separated, it was big news around the world.
With so much drama in his life lately, it's as if the 25-year-old from Northern Ireland has eliminated all the suspense in his game. Following a win at Wentworth, he absolutely torched Muirfield Village. He had eagles at 11th and 15th holes and tossed in seven birdies, breaking the first-round mark held by three players - despite a double-bogey at the 14th.
''I don't think it's anything more than just being confident with my game,'' he said.
What's more, McIlroy did it despite injuring his left knee on his second shot at the par-5 seventh hole. He hobbled for the next few holes, continually flexing it in between shots.
''I wear spikes, so sometimes your foot can get stuck in the ground and you can torque your knee a little too much,'' he said. ''The inside of it is sore, a little swollen. I'll go (to the fitness trailer) and get some treatment and get ice on it and hopefully it'll be OK for tomorrow.''
He'll have to be healthy to keep ahead of a stellar leaderboard.
Masters champ Bubba Watson led the trio in second. Paul Casey, playing at Muirfield Village for the first time since 2009, also had a 66, along with Chris Kirk.
Watson said he's learning to juggle fame, his job and his home life.
''It's a learning process. It took me a while to learn it,'' he said. ''That doesn't mean I'm going to play good the rest of my life. But right now I'm handling it and I understand what it takes to be a dad and husband. That's the main goals. Those two things come first before golf.''
Keegan Bradley, playing with a regulation-sized putter instead of an anchored, longer model as he usually does, was at 67 along with Michael Thompson and J.B. Holmes. Justin Leonard - recording his best round at the Memorial in 12 years - shot a 68, as did Hunter Mahan and Ryan Moore.
World No. 1 Adam Scott was at 69 and Phil Mickelson, trying to turn things around at a tournament where he has seldom contended, closed bogey-double-double for a 72.
About the only notable name not near the top of the scoreboard was Tiger Woods, the five-time Memorial winner who is sidelined after back surgery. He's out at least through the U.S. Open in two weeks at Pinehurst.
The way things are going for McIlroy after a rocky few days, it would be difficult for anyone to slow him down.
He had 14 one-putt greens, needed just 22 putts for the round, holed five of at least 10 feet and made all 16 putts he attempted inside 15 feet.
''I really think I've found something,'' he said.
The only blip in his round was the double at 14, where he was forced to play away from the hole with a sand shot and ended up leaving it in the trap.
After announcing last week that he and Wozniacki had called it quits, McIlroy turned off his cellphone and gave away his laptop. While rumors and innuendo flew, he tried to just concentrate on his game.
Then came the win at Wentworth. And that led to what he did Thursday.
''(There's a) confidence that a win gives you,'' he said. ''I'm not saying the game feels easy, but you're on a roll where you have momentum. I'm used to winning enough now. I know how it feels. There shouldn't be a letdown. It's just keep it going, keep doing the right things and keep shooting low scores.''
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