Woods and Mickelson drawn together for opening rounds

CHICAGO, Aug 14 (Reuters) World number one Tiger Woods and defending champion Phil Mickelson have been drawn together for the opening two rounds of this week's U S PGA Championship, the fourth major of the season.

Joining the American pair on the opening tee in Illinois on Thursday will be Australia's Geoff Ogilvy, pitting the winners of the first three majors of the season against each other for the first 36 holes.

Mickelson won the U S Masters in April for his third major title, Ogilvy claimed the U S Open in June, while Woods stormed to his 11th grand slam victory at the British Open last month.

The season's final major takes place at the ultra-long tree-lined Medinah Country Club's No. 3 Course, where Mickelson will be hoping to defend the title he won after going wire-to-wire for at Baltusrol.

The trio will tee off at 1330 GMT on Thursday and 1835 on Friday.

Woods will be seeking his third PGA Championship after winning at Medinah and 1999 and defending successfully at the Valhalla club.

Two-time PGA Champion Vijay Singh of Fiji will join fellow past champions John Daly and Jeff Sluman of the U.S. in an afternoon group on the first day.

South Africa's Ernie Els will tee off two groups ahead of Singh's threesome at 1815 GMT with Spain's Sergio Garcia and American veteran Fred Couples.

REUTERS DH HT1632