VIRGINIA WATER, England -- Rory McIlroy could only manage a disappointing 2 over par 74, while defending champion and former No. 1 Luke Donald slumped to a 78 on a rain-affected first round of the BMW PGA Championship on Thursday.
South Africa's James Kingston led the field after finishing with a 6 under 66 before play was interrupted by a 90-minute rain delay during the afternoon. Later, five groups were yet to finish as darkness fell and play was suspended.
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Kingston had a one-stroke lead over Finland's Mikko Ilonen, with Scotland's Scott Henry and Gonzalo Fernandez-Castano of Spain tied for a share of third place after both carded 68s.
"I feel as though I am playing well enough, but it is just not being reflected on my scorecard," said McIlroy, whose total included 33 putts. "I played the first 12 holes really not missing a shot, but I just feel at the minute I am not getting that much out of my rounds."
The Northern Irishman, who played in the company of his Ryder Cup winning teammates Graeme McDowell and Paul Lawrie, was 3 under after 12 holes before carding three bogeys in succession from the 13th.
The double major winner then parred the 16th, but dropped further shots at 17 and 18.
"I'm not sure what the problem is because, as I said, the first 12 holes was really good golf and very solid, but I just got on a run of bogeys and couldn't get off it," McIlroy said.
His effort continues a disappointing first-day trend at the European Tour's flagship event. He shot a 74 on day one of the tournament last year, a 76 the year before, and a 74 on the opening day of the 2010 BMW PGA Championship.
Also signing for a 74 was fellow U.S. Open winner and Northern Irishman Graeme McDowell, who ended with an 18th hole double bogey -- having taken a triple bogey at the same hole on day one of the 2012 event.
Donald produced just one birdie, but also had five bogeys and a double bogey as he recorded his poorest round at Wentworth since a 74 on the first day of the event in 2009.
"It is disappointing to be this far back after one round but then that's just golf, again," Donald said. "Today was quite different to how the course has played in the past but I just didn't do very well in adjusting."
Kingston, ranked 297th and playing on a sponsor's invitation, capped his round with four birdies over his closing seven holes. It was his lowest Wentworth score by one stroke after shooting 67 twice on his debut in 2003.
"Receiving an invitation into this event was nice, and what a great feeling to be back here," he said. "I played nicely and got off to a decent start and really made the putts when I needed to."
Ilonen marked his 10th appearance at Wentworth with a tournament-best round of 67, having finished runner-up in his last event, the Volvo China Open.
"I've had good form this year but then Wentworth has not been the best of places for me," Ilonen said.
Among the 15 players who will complete their rounds on Friday morning is Austria's Martin Wiegele, the last player to tee off. He was 4 under with still five holes to play.