Rory McIlroy has made a steady start in his bid to secure a third successive major win at the Masters at Augusta.
McIlroy fired three birdies and two bogeys in a one-under-par 71, to lie seven shots behind leader American, Jordan Spieth, who recorded a fine 64
The world number one is aiming to become the sixth man to win all four majors but has only one top-10 finish in six previous visits to the Masters.
Graeme McDowell is also one under, with Darren Clarke further back on two over.
European Ryder Cup captain Clarke had double bogeys at the fifth and seventh holes, but birdies at the sixth and 15th helped him retain hope of making the halfway cut.
McDowell posted five birdies and four bogeys, including a dropped shot at the 18th, to stay in contention.
Charley Hoffmann, Justin Rose, Jason Day and Ernie Els are three adrift of the impressive Spieth.
McIlroy had to work hard on a scorching morning at Augusta National, but will know that his challenge is very much alive.
|Golf's Grand Slammers|
|Gene Sarazen||Slam completed in 1935, aged 33|
|Ben Hogan||Slam completed in 1953, aged 40|
|Gary Player||Slam completed in 1965, aged 29|
|Jack Nicklaus||Slam completed in 1966, aged 26|
|Tiger Woods||Slam completed in 2000, aged 24|
The Northern Irishman opened out with a huge 324-yard drive down the first but found the water hazard on the par-five second, scrambling superbly for par with a beautiful back-spinning chip to within four feet.
Having dropped a shot on the par-three sixth, he then hit straight back with a fine approach on the seventh for his first birdie of the tournament, but another bogey on the testing par-four 11th slowed his momentum.
A birdie on the par-five 13th was followed by a wonderful 21-foot birdie putt on the 15th, and he was a little unlucky that his tee-shot on the par-three 16th failed to release down the slope of the green.
"It was a solid start and a decent score - it could have been better, but it could have been worse," observed McIlroy after his opening round.
"I put myself in some difficult positions but I battled well and holed some nice putts. I'll try to stay as patient as I can and pick off the birdies where I can."
Three-time major champion Padraig Harrington is level par, with fellow Irishman Shane Lowry three over on his first appearance at the event.