- Rory McIlroy and Keegan Bradley share the lead at the PGA Grand Slam
- The Bermuda event pits the year's four major winner against each other
- McIlroy and Bradley on four-under, with Charl Schwartzel on four-over
- Darren Clarke three shots adrift of South Africa's Schwartzel
U.S. Open champion Rory McIlroy and PGA Championship winner Keegan Bradley share a seven-shot lead after the first round of the PGA Grand Slam in Bermuda.
McIlroy, 22, and American Bradley both carded four-under-par opening rounds of 67 at the event which pits the year's four major winners against each other in a two-round tournament.
Masters champion Charl Schwartzel is seven shots back on three-over, with McIlroy's fellow Northern Irishman Darren Clarke, who won July's British Open, fourth on six-over.
It is the first time since 2003 that four first-time major winners have competed in the event; with world number three McIlroy looking to become the youngest winner in the tournament's 29-year history.
McIlroy was pleased with his form on the back nine after finding himself five-shots adrift of Bradley, 26, at one stage of the round.
"I'm driving the ball great," McIlroy told the European Tour's website. "To birdie four of the last seven holes was huge as I was five behind Keegan at one stage.
"Then again I gave myself so many chances on the front nine -- I found the greens very difficult to read -- so it was great to make up that ground and finish birdie-par when the weather turned wet and windy."
Bradley was in imperious form at the start of his round, hitting two eagles and three birdies to sit six-under for the front nine.
"The two six irons I hit to set-up the two eagles were two of the best shots I've hit all year," world No. 26 Bradley said. "I slowed down on the back nine but it was still a great day."
South Africa's Schwartzel hit two birdies during his round of 74, but let four other opportunities to gain a stroke slip through his grasp.
"I'm very disappointed," the 27-year-old said. "I played really well until I three putted the 12th then missed short putts on the next two greens."
Clarke, 43, was upset with his form, admitting he has struggled with his game since lifting the Claret Jug three months ago.
"I'm struggling with my swing and my ball striking," said Clarke. "I've not hit the ball very good since the Open Championship. I saw a couple of things in my swing I didn't like and which I tried to fix.
"It seems to have gone the other way! I didn't come all this way to play that badly and it is very disappointing."
The second and final round at the Port Royal Golf Course in Southampton will take place on Wednesday.