CHICAGO (AFP) - Third-ranked Rory McIlroy and England's Paul Casey made early charges on Friday (Sept 9) but American Roberto Castro remained in the lead after the storm-interrupted first round of the US PGA Tour BMW Championship.
Castro, seeking his first PGA title after two runner-up efforts, opened with a seven-under 65 Thursday at Crooked Stick in Indianapolis to lead compatriot Brian Harman by one stroke.
US major winners Dustin Johnson, the world number two who won the US Open in June, and Jason Dufner reached the clubhouse on 67 on Thursday before darkness fell.
Lightning and heavy rain halted play for three and a half hours, forcing 36 of 70 players to finish the first round on Friday morning.
Casey eagled the par-5 ninth hole on Thursday but made his lone bogey at the par-3 13th. On Friday he added birdies on 15 and the par-3 17th to open on 67.
"You have to hit a lot of greens in regulation," Casey said. "I think that's the key."
Also on 67 were American William McGirt and Canada's David Hearn, who birdied the par-5 11th and 15th as well as 13 and answered a bogey at 16 with a chip-in birdie at 18.
"Definitely gives me a lot of confidence going into the afternoon on a shot like that," Hearn said.
McIlroy, who won last week at Boston, was three-under after 10 holes when dusk arrived Thursday then made bogey Friday at the par-5 11th, missing the green with his approach and failing to sink a seven-foot par putt.
But the Northern Ireland star birdied the par-5 15th and par-4 18th to finish on 68 alongside Argentina's Fabian Gomez, Japan's Hideki Matsuyama and Americans Chris Kirk, Matt Kuchar, Brooks Koepka, Jordan Spieth and Phil Mickelson.
World number one Jason Day of Australia, the defending champion, opened on 73 to stand eight adrift in a share of 48th.
The event will determine the 30 qualifiers for the season-ending Tour Championship in two weeks at Atlanta.
Each of the 30 will have a chance to win a US$10 million (S$13.5 million) playoff bonus, but the five points leaders based upon season results will have the best opportunity for the prize by simply winning no matter how rivals fare.
US star Patrick Reed leads the points chase followed by Day, Johnson, McIlroy and Aussie Adam Scott.