(AFP) - Patrick Reed and Martin Laird fired five-under 66s to open up a one-shot lead after the first round of The Barclays Championship on Thursday.

World No. 14 Reed rattled off 10 consecutive pars over the opening 10 holes before hitting three birdies and an eagle over the final eight holes at Bethpage Black in Farmingdale.

Reed's impressive opening round left him sitting pretty alongside Scotland's Laird after a first round that saw Sweden's Henrik Stenson limp out injured.

Reed, who teed off on the back nine, grabbed the first of his three birdies on the second, before eagling the par-five fourth hole with a 16-foot putt.

Further birdies on six and seven completed a flawless display for the 26-year-old from San Antonio, who is chasing a fifth PGA Tour victory.

Laird meanwhile also produced a blemish-free round, carding a 66 after sinking five birdies and no bogeys.

Laird and Reed finished ahead of a group of four players on four under, which included Rickie Fowler.

Fowler's round included three birdies and an eagle and would have been good enough for a share of the lead had it not been for a bogey on the par-four ninth, when his second shot landed in the front bunker.

World No. 1 and defending champion Jason Day of Australia meanwhile was two off the pace, after a 68.

Day recovered from a bogey on the second to carve out four birdies and 12 pars for his three-under-par total.

But it was a disappointing return to the day job for newly crowned Olympic champion Justin Rose of England.

Rose, who won the gold medal in Rio de Janeiro as golf made its return after a 112-year absence, shot a two-over 73 after an erratic first round.

Rose appeared to be in good shape after back-to-back birdies on the seventh and eighth. But a bogey on the ninth was followed by four more on the back nine to leave him seven shots off the pace.

Sweden's Stenson - silver medallist behind Rose in Rio - also gave Europe a Ryder Cup scare after withdrawing with a knee injury.

World No. 4 Stenson, who carded a three-over 74, said he had aggravated an old problem.

"My right knee, which required surgery in December, 2015, has flared up again," Stenson said in a statement.

"Regrettably, I need to withdraw this week to allow time for an MRI and see what the next step is."