Rory McIlroy declared himself happy with his first round 69, knowing it could have much worse.
The 20-year-old from Holywood, who won the Silver Medal for leading amateur at Carnoustie two years ago, had five bogeys on his card and a double bogey six.
After his excursion into the heavy rough on the par-four eighth, he immediately bounced back with a birdie and then two more to finish with a one-under 69.
“There was a bit of good, a bit of bad and a bit of ugly,” he admitted.
“I thought I played very solidly. I had eight threes on my scorecard, which is good around here, good around any golf course.
“And I hit the ball a lot better today than I have been the last week or so. I've only missed a few fairways and the couple of fairways that I did miss cost me a double bogey and a bogey.
“So if you're just slightly off your game, you can make a couple of big numbers, but then if you're on your game you can make this course look very easy today, which some people did.”
England's Paul Casey knows he failed to make the most of his excellent start, but remains upbeat about his chances.
He was three under after five and even after a bogey he eagled the seventh to go four under, but dropped shots at the 12th and 14th to fall four strokes behind leader Miguel-Angel Jimenez.
“It was frustrating but this golf course can jump up and bite you very quickly,” he said.