Singh won his 12th PGA Tour event a month before his 40th birthday in 2003 and since then has won 22 more times. His 63 Thursday was his best round on the tour since he fired a 61 at the 2006 Deutsch Bank Championship, where he eventually finished second.
He birdied six of the last eight holes at the Old White-TPC course in a bid to win on the tour for the first time in four years.
There were 62 sub-par scores turned in during the opening round. Defending champion Scott Stallings had a 67.
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