Woods birdied his first hole in sensational fashion by sinking a 60-foot putt, but he struggled the rest of the way to a 3-over 73, seven shots behind leaders Nick Watney, Jason Day, Joe Ogilvie and Arjun Atwal.
Woods said afterward that although he hit only 57 percent of his fairway shots, he was more concerned with his "awful" putting.
"My speed was good, but I never hit the ball on line," Woods said. "It was a very frustrating day on the greens, especially how good I was driving it."
The leaders turned in rounds of 4-under 66 at the Aronimink Golf Club near Philadelphia. Another six players were deadlocked at 3-under 67.
The 6,955-yard course featured challenging pin positions and an unforgiving rough that kept the field on a short leash.
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