Ben Curtis birdied the ninth, his final hole, to snatch a one-shot lead at the halfway mark of the Booz Allen Classic in Potomac yesterday.

The first round leader added a second round 65 for a 15-under-par total of 128 and a one-shot advantage over Argentina's Jose Coceres.

Jeff Gove is on 11-under-par after a 68 while Ben Quigley fired a 63 to share fourth place with John Huston. JB Holmes was a further shot back at nine under after shooting a 66.

Padraig Harrington also moved up after a second-round six-under-par 65 left him eight shots off the pace on 135.

The Dubliner went to the turn in 31 with the help of four birdies and added two more at the 11th and 13th before dropping his only shot at the par-three 17th.

However, he hit back immediately with a birdie at the last for a round of 65.