Jordan Spieth got the defence of his Masters Tournament title off to a brilliant start on day one at Augusta National, but he will have to hold off a strong chasing pack full of European Tour Members if he is to take the lead into the weekend.
The World Number Two fired a sparkling 66 to open up a two-shot lead over Danny Lee and Shane Lowry, with Sergio Garcia, Søren Kjeldsen, Ian Poulter and Justin Rose in the group a further shot back.
Rory McIlroy, chasing a career Grand Slam of Major Championships, and Danny Willett were then in the group at two under.
Spieth was unblemished in getting to six under as he looks to become the first man to successfully defend the title at Augusta National since Tiger Woods in 2002.
It had looked like Jason Day would provide his main opposition as the Australian turned in 31, but the World Number One came back in 41 to slip back to level par.
After a good up-and-down to save par on the first, Spieth birdied the third and sixth before putting his approach on the eighth to four feet for another gain. Further birdies followed on the tenth and 13th, and a closing gain put him in control on a windy day.
"I would have signed for two under today and not even played the round, knowing the conditions that were coming up," he said. "I got a lot out of the round with what I felt like was average-ish ball striking. I just scored the ball extremely well, which is something I've been struggling with this season.
"I feel like my game's been trending in the right direction, I just haven't gotten scores out of how I felt I'd been playing. That normally just comes down to putting. Certainly made a lot of putts today.
"If I can kind of straighten things out with the iron play, hopefully we'll be in business.
I am extremely pleased with that round today. I felt like we stole a few - Jordan Spieth
"I think that everything that we do is building up around the Major Championships, and so we are trying to peak this week."
Lowry started with a par but then went on a brilliant run as he picked up shots on the second, third, fourth and fifth before another birdie followed on the eighth.
The Irishman then dropped a shot on the 12th to sign for a 68 alongside Lee, who recorded six birdies and two bogeys.
Rose made six birdies on his way round but also had three bogeys in a 69, with Paul Casey also dropping three shots with six gains.
Poulter turned in 34 with three birdies and a bogey but back-to-back dropped shots on the tenth and 11th got him back to level par before he picked up shots on the 13th, 14th and 16th.
Garcia and Kjeldsen both came home in 32 after being one over at the turn. Garcia made a run of four birdies from the 13th, while Kjeldsen had gains on the 12th, 14th, 16th and 17th.
McIlroy dropped shots on the 16th and 18th to fall back late in his round, with Willett recording a single bogey on the last.
