World number one Woods seeks his 15th major title, which would put him three shy of the career record 18 won by Jack Nicklaus, and a fourth US Open crown to match the record held by Nicklaus, Ben Hogan, Bobby Jones and Willie Anderson.
Hearty supporters braved intense showers to surround the first tee as a super group of reigning major champions teed off just after 8 in the morning, all three clad in black rain gear that matched the dreary skies above them.
British Open and PGA Championship king Padraig Harrington of Ireland smacked his ball into the fairway. Masters champion Angel Cabrera of Argentina blasted his first tee shot long and into the dense rough on the dogleg right hole.
Woods followed by hooking his tee shot way left into a concession stand area and stared in stunned disbelief for several moments before gathering himself and starting a sloshy trek around the public course where he won the 2002 Open.
Woods blasted to a bunker but rescued a par while Cabrera and Harrington opened with bogeys, the Irishman three-putting.
Maintenance crews were frantically squeegeeing holes and trying to keep the course from becoming unplayable due to the showers, which are expected to last throughout the tournament and worsen into thunderstorms this weekend.
Woods also could become the first player to defend all four major titles - a "Back-to-Back Slam". He won the PGA Championship in 1999 and 2000, the Masters in 2001 and 2002 and the British Open in 2005 and 2006.
Not since Curtis Strange in 1989 has a player won consecutive US Opens. Woods limped to victory in last year's US Open at Torrey Pines, defeating Rocco Mediate on the first sudden-death hole following an 18-hole playoff.
Left knee surgery and an eight-month layoff followed but Woods has won twice since his return in February, including two weeks ago at the Memorial in his final US Open tuneup, where he hit every fairway in the final round.
Phil Mickelson, a three-time major winner but a four-time US Open runner-up who has never won this event, tees off in the afternoon as he tries to set aside his concern for wife Amy, who faces breast cancer surgery in a few weeks.
Mickelson, a fan favorite at Bethpage, will try to fulfil his wife's wish of having the championship trophy in her hospital room.
Japan's Ryuji Imada shared the early lead at one-under after four holes as birdied on the 10th hole, their first of the day, pulled New Zealand's Michael Campbell and Argentina's Anders Romero level. Campbell won the 2005 US Open.
Source: http://uk.eurosport.yahoo.com