For Rory McIlroy, the shockingly bad shot came out of nowhere.
By the time he walked off the 18th green, there was little doubt he was still the man to beat at the PGA Championship.
McIlroy ripped off four straight birdies on the back side and closed with another at the 18th hole, shooting a 5-under 66 at Valhalla that left him one shot off the lead this morning (NZ time).
Coming off wins at the British Open and Firestone, McIlroy came into the final major of the year as an overwhelming favorite.
Even with a major blunder at the 10th, where he knocked his second shot over a fence and took double bogey, he was right on the heels of Lee Westwood, Ryan Palmer and Kevin Chappell.
''I'm really happy with everything,'' McIlroy said.
''I've got a good thing going right now. I'm trying to ride that momentum as much as I can.''
Then there's Tiger Woods, who can't seem to get anything to go his way.
Playing just four days after his back flared up at Firestone, forcing him to withdraw, Woods proclaimed himself fit but sprayed shots all over the course on the way to a 74 that left him tied for 111th late in the day.
He looked very much like someone playing just his 11th competitive round since back surgery in late March, someone who had his worst 72-hole finish in a major at the British Open last month.
''That wasn't very good,'' said Woods, who made only one birdie - and had to hole out from the fairway to do that. ''A lot of bad shots.''
One landed in a creek. Another sent the gallery scrambling. Yet another rolled into a fenced-off area where fans can use cellphones, a good 30 yards right of the fairway.
Too bad Woods couldn't call for help.
''I didn't play as well as I wanted to. I didn't get a putt to the hole,'' he said. ''That's not a good combo.''
McIlroy was cruising along when he got to the 10th, having made three birdies on the front side.
After putting his tee shot right in the middle of the fairway at the par-5 hole, he yanked the next one out of bounds. A man talking on his cellphone along the fence, not concerned at all with getting in the way, was stunned with he looked up to see a ball sailing over his head.
Especially when he learned whose ball it was.
''I was really annoyed,'' McIlroy said. ''That second shot at 10 is the worst shot I've hit in weeks. It came out of the blue.''
He took a penalty and a drop and missed the fairway with his next attempt as well, resulting in a 7.
Still shaken by that miscue, McIlroy made a bogey at No 11 to slip to even on the day. Then, just like that, he pulled himself together.
Four straight birdies pushed McIlroy right back up the leaderboard, and it could have easily been five in a row. A 12-footer slid over the edge of the cup at the 16th.
At the final hole, McIlroy reached the green in two for an eagle try to share the lead. If curled off at the end, leaving him with a tap-in - his eighth birdie of the round.
''It could have been better,'' he said. ''But a 66 the first day, that's a solid start.''
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