USPGA Championship update: Robert Karlsson and Jeev Milkha Singh were confirmed as first round co-leaders of the 90th US PGA Championship today as the rain-delayed opening day's play was finally completed at Oakland Hills.

Play had been suspended for 85 minutes yesterday evening, leaving 18 players out on the course by the time darkness prevented further play.

Karlsson and Singh had posted early two-under-par rounds of 68 before the weather interruptions but Argentina's Andres Romero was out on the course at two under with two holes to play when play was called to a halt.

Romero returned this morning but bogeyed the par-four 18th, the toughest hole on the course in the first round, to post a 69, one shot back from the leaders in a group of five also containing Spain's Sergio Garcia and the Americans Ken Duke, Billy Mayfair and Sean O'Hair.

Eight players were starting their second rounds at level par, including world number two Phil Mickelson, the 2005 PGA champion, 2007 US Open champion Angel Cabrera and Anthony Kim, the young American with two PGA Tour wins to his name this year.

British Open champion Pádraig Harrington did complete his opening round last night, coming home with a one-over-par 71 that kept him in touch with the leaders and he was one of the early starters today.

Harrington started at the 10th and quickly made a birdie but immediately gave the shot back with a bogey at the 11th, his second. The Dubliner was still level for his round after six holes and three off the lead at one-over.

Darren Clarke was also another early starter and the Dungannon golfer is flirting with the projected cut mark. The 39-year-old was level for the day after six holes but remains on five-over after an opening 75, one shot outside the cut.

Graeme McDowell is the third Irishman in the field and he too will look to make up ground after an opening 74. The 29-year-old tees off at 6.50pm (Irish time).