Tiger Woods takes one hand off the club after playing a shot on the sixth hole during first-round play at the British Open Thursday. Tiger Woods takes one hand off the club after playing a shot on the sixth hole during first-round play at the British Open Thursday. (Alastair Grant/Associated Press)

As always at the British Open, the weather figures to be the biggest factor.

Golf's oldest major began Thursday morning in Scotland under threatening skies with a tee shot by 1999 champion Paul Lawrie. Light rain started falling about an hour later, and an even more ominous storm was bearing down on St. Andrews as some top players prepared to tee off.

Tiger Woods won at the Old Course in 2000 and 2005, and he's again a heavy favourite as the Open returns to the birthplace of golf. Still, the world's No. 1 player has yet to win since returning in April from a five-month layoff stemming from scandalous reports that he cheated on his wife with multiple women.

A steady rain soaked the course on Wednesday, forcing officials to postpone the Champions' Challenge. Twenty-six former winners were scheduled to play a four-hole exhibition, with the winning team earning $76,000 US for its designated charity. The money went to Seve Ballesteros's foundation, honouring the former champion who's battling brain cancer.

Lawrie, who rallied to win at Carnoustie after Jean Van de Velde's epic meltdown on the 72nd hole, opened with a tee shot down the middle toward the famous Swilcan Burn. John Daly, the surprising winner at St. Andrews in '95, birdied the first two holes and was among the early leaders with 55-year-old Loren Roberts and Germany's Marcel Siem.

With speculation about his private life swirling around, Woods was to tee off at mid-morning — not long before the heavy rains were projected to arrive — in a group that included English favourite Justin Rose, who has won two of his last three PGA Tour events and is trying to become the first British golfer to win the Open since Lawrie.

Woods has 14 major titles, just four off the career record held by Jack Nicklaus.

Playing in the group right behind Woods and Rose were two-time champion Padraig Harrington, looking for his first sanctioned tournament win since capturing a third major title at the 2008 PGA Championship. Tom Watson, 60, who nearly became golf's oldest major winner at Turnberry a year ago, joined Harrington.

Watson would have claimed the claret jug for the sixth time if he had made an 8-foot putt on the final hole of regulation. After missing, he lost in a four-hole playoff to Stewart Cink.

The defending champion was set to play the first two rounds with Ernie Els of South Africa and Ian Poulter of England.

Woods has been atop the world rankings for more than five years, but Phil Mickelson can take over the No. 1 ranking for the first time in his career if he wins this week. Lefty captured his third Masters title in April, contended at the U.S. Open and believes his long-hitting game sets up well for the Old Course.