Roberto Castro fired a seven-under par 65 to grab a one-stroke lead over fellow American Brian Harman after darkness halted Thursday's opening round of the US PGA BMW Championship. Castro, seeking his first PGA title, birdied the second and fourth holes and added another at the par-5 ninth for a solid start, then birdied six of the final nine holes only to take a bogey at 18 to halve his edge.
