Hampshire's Justin Rose did not fully capitalise on a brilliant start, slipping one stroke behind American leader Jonathan Byrd after the opening round at the £2.5million BMW Championship on Thursday.

Rose, one of just three British players in the 66-man field, was in superb form as he carded eight birdies in the first 11 holes at Cog Hill.

At eight under par, he had a four-stroke lead at one stage, but could not maintain the momentum, running up two late bogeys for a six-under 65.

Rose said: "It was a dream start today. I hit a few shots close, had some nice little tap-ins and was four-under through six holes without making a putt.

"It's always disappointing when you're eight under through 11 and you finish six under but it's certainly not an easy course. There were some tough holes coming in and I was a little bit in between clubs.

"The front nine I had good yardages, was able to hit aggressive shots, and on the back nine the wind was gusting and I had to be slightly more defensive".

Rose ever so briefly contemplated the thought of shooting the magical 59, but just as quickly realised it was probably the worst thing to do.

"When you're playing well and staying in the moment, you're not getting ahead of yourself and I was doing all those things today," he said. "That's one of the reasons I played well".

Despite his lofty world ranking of 15, Rose is still seeking his first American victory, and he hardly could have hoped for a better start.

He was on song with his iron play from the off - his first four birdies little more than tap-ins, before his putting also came good as he sank a 15-footer at the par-four seventh and a 45-footer at the par-five ninth.

Making the turn at six under, he continued to attack on the back nine, adding birdies at the next two holes, sinking a 20-footer at the par-four 10th, before two-putting at the par-five 11th.

But the birdies dried up after that, with bogeys at the par-five 15th and par-four 18th not exactly what he had in mind.

Compatriot Ian Poulter also had a nice round, shooting a three-under 68, but Luke Donald struggled to a disappointing 76.

Byrd, meanwhile, birdied three of his final four holes to lead Rose and Colombian Camilo Villegas by one stroke, with Tiger Woods equal seventh on four-under 67.

This event is the third in the new four-tournament FedEx Cup play-off series. Only 30 players will advance to next week's Tour Championship.

Rose, ranked 23rd, is certain to be among them, while Donald, currently 28th in the standings is in danger of falling out of the top 30.