Schwarzrock is tied with Tom Scherrer, who carded a bogey-free 66. Scherrer was in contention through two rounds of this year's AT&T Pebble Beach National Pro-Am, but posted rounds of 73-80 over the weekend to tie for 55th.
Tournament favorite Tiger Woods is five off the pace after opening in even-par 71. Tiger, who has never won in six prior Nissan starts, offset three birdies with three bogeys.
Thursday, Schwarzrock carded seven birdies and two bogeys. Ironically, after beginning the day with a birdie at the par-5 first, Schwarzrock recorded a pair of bogeys on each of the remaining par-5s.
Schwarzrock is in his third season on the PGA Tour. He first qualified in 1999 after finishing 11th in the '98 Qualifying Tournament, but managed to only complete one round the entire season due to a reoccurring back injury.
Still hampered by an ailing back, Schwarzrock played in 19 events on the PGA Tour in 2000 thanks to a medical extension. He made six cuts and finished 195th on the season-ending money list.
A tie for 31st at this past year's Qualifying Tournament gave a healthier Schwarzrock a reprieve in 2001. Thus far, he's competed in three events, making two cuts.
The 28-year-old Sea Island, Ga., resident is one shot clear of a host of other players. Included in the mix are Japanese standouts Joe Ozaki and Shigeki Maruyama, each of whom opened in 4-under-par 67. Australian Bradley Hughes also posted a first-round 67; as did American Edward Fryatt.
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