CHICAGO • American Roberto Castro upstaged some of the biggest names in golf to take a one-shot lead at the rain-hit BMW Championship with a seven-under 65.

Defending champion Jason Day was eight strokes back after a 73 on Thursday. FedExCup points leader Patrick Reed managed a 70 while Rory McIlroy, winner of the Deutsche Bank Championship on Monday, was three-under after 10 holes.

Castro reeled off eight birdies before missing a six-foot par putt at the 18th at Crooked Stick in Carmel.

"I started off pretty well," he said. "Got going coming back and was thinking about birdies."

Lightning and heavy rain in the Indianapolis area stopped play for 3hr 31min, leaving the late threesomes in the field of 70 no hope of finishing before sunset.

Castro was among 33 players who completed their rounds in the third of the PGA Tour's four FedExCup play-off events.

Compatriot Brian Harmon trails by one stroke, while Major champions Dustin Johnson and Jason Dufner shot 67s and sit two back.

US Open champion Johnson was challenging for the lead until making bogey on the par-four 18th.

Castro is hoping to make a name for himself on the same Pete Dye-designed course where long-hitting John Daly emerged from obscurity to win the 1991 PGA Championship. He said he tends to thrive on courses with danger lurking at every corner.

"I do better on tougher courses sometimes," he told reporters. "It snaps me into focus."

REUTERS, AGENCE FRANCE-PRESSE

BMW CHAMPIONSHIP

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