Nasty weather, however, threatens to spoil the first round of the much-anticipated tournament, which for the first time in 32 years will be contested at the Merion Golf Club.
It was also where Ben Hogan won his second of four U.S. Open titles in 1950 barely a year after he suffered critical injuries in a near-fatal auto crash.
The best players in the world will be on hand with the first ball scheduled to be struck at 6:45 a.m. by Cliff Kresge, a golfing journeyman who has not been fully exempt on the PGA Tour for three years.
Kresge was one of almost 10,000 golfers who took part in qualifying tournaments around the country, and those who survived will play alongside golf's household names -- 22 of whom have won at least one major title.
Woods has won four times on the tour this year in his return to the No. 1 ranking, but he has not won a major championship since he captured this event in 2008 with a playoff victory over Rocco Mediate.
More than 5 inches of rain struck the course from last Friday through Monday, after which the sun came out for Tuesday and Wednesday as workers swarmed over the layout to make it playable.
Additional rain was in the forecast for Thursday with hail and damaging winds also possible. Forecasters said the chance of rain was 100 percent.
The rest of the weekend is expected to be dry, but a major rain event Thursday could wind up extending the tournament through at least Monday.