SOUTHPORT, England -- From sunny San Diego to bleak and blustery Royal Birkdale, the expression on Rocco Mediate's face didn't change.

He watched one final birdie tumble into the cup for a 1-under 69 and a three-way share of the lead in the British Open, straightened his 45-year-old back, then dropped his jaw into a smile that said, "How did that just happen?"

Others must have been wondering the same thing Thursday.

Ernie Els was playing some of his best golf in the worst of the weather until taking 45 shots on the back nine and posting an 80, his highest score in nearly two decades at his favorite major.

Phil Mickelson was up to his knees in grass right of the sixth green and never found his ball, taking a triple bogey that sent him to a 79.

Robert Allenby and Graeme McDowell, who watched on television as the early starters suffered through raging wind and stinging rain coming off an angry Irish Sea, must have wondered where all that nasty weather went as they made their way around Birkdale in tamer wind to join Mediate atop the leaderboard.

Stranger still was seeing 53-year-old newlywed Greg Norman in the hunt.

Indeed, how did all that happen?

"I have no explanation for that whatsoever. No idea why that happened," said Mediate, still going strong after his epic playoff loss to Tiger Woods last month in the U.S. Open.

"It was just one of those rounds," he said. "It was just up and down, up and down, and a couple of birdies, and here we are. I would have been ecstatic with 73 or 74 today."

Norman made enough par-saving putts to sustain momentum and finish at 70 along with Australian protege Adam Scott and Bart Bryant.

The group at 71 included Retief Goosen, who might have played the best golf of anyone.

Goosen awoke at 2 a.m. when rain pelted his windows, and he caught the brunt of the bad weather his entire round. He still managed four birdies and was under par most of the round until a pair of late bogeys.

"How in the hell is he 1 under?" Pat Perez said from the warmth of the locker room after an 82. "I would pay to learn how to do that."

The leaders caught a break by getting slightly better weather, although it was by no means easy. The average score in the opening round was about 76, driven up by 19 rounds in the 80s.

The British Open lived up to its billing as the major that sometimes requires the most luck.

It wasn't a goofy bounce but the tee times, thanks to weather that shifted along with the tide in the middle of the 15 hours of action.

"We did get the better side of the draw, no doubt about it," Norman said. "When you watch it in the morning, you feel sorry for the guys. But there's times when you say, 'Well, I've been there before. I've been on that side of the draw, too.' It all balances out, and you have to take advantage of it."