Godfrey fired a seven-under-par 63 at East Lake Country Club in Atlanta, GA to break the U.S. Amateur record for lowest 18-hole score in a qualifying round. Phil Mickelson established the previous mark of 64 at Meridian Golf Club in 1990 and Hank Kim matched it at the TPC at Sawgrass in 1994.
Godfrey's 63, which included three straight birdies at the start, also tied the course record at East Lake set by Vijay Singh at the 1998 Tour Championship.
'If you would have told me I would shoot a 63 yesterday, I'd say you're crazy,' said Godfrey, who is appearing in his first U.S. Amateur after failing to qualify in four previous attempts. 'I'm just hoping to reach match play. It's rough out there playing with these college kids.'
The second and final round of stroke play will be held Tuesday, after which the low 64 scorers from the starting field of 312 advance to the match-play portion of the competition.
The 36 holes of stroke play are divided between the 7,091-yard, par-70 East Lake layout and nearby Druid Hills Golf Club, which at 6,561 yards and a par 72, played much easier than East Lake on Monday.
Of the 77 players who finished the day at or under par, only 21 played at East Lake. The East Lake course will host all five days of match play, including Sunday's 36-hole final.
Lucas Glover, 21, of Greenville, South Carolina, shot an eight-under-par 64 Monday at Druid Hills.
'My goal was not to make any bogeys, and I didn't,' said Glover, a two-time All-American at Clemson University.
Opening with a 64 at East Lake was James Driscoll, last year's U.S. Amateur runner-up, who was a teammate of Glover's on the U.S. Walker Cup squad that lost to Great Britain and Ireland last week at Sea Island, Georgia.
Driscoll, who was 0-3 in his matches versus GB&I, was pleased to rebound with a solid round on Monday.
'I felt great,' he said. 'I wish I was a little more solid on a couple holes there on the back nine, where I hit some weak shots but made up for it with my short game. But I was glad to see my short game was there to back me up when I didn't hit a great shot.'
Defending champion Jeff Quinney, who sank a 30-foot birdie putt on the 39th hole to defeat Driscoll in the final last year at Baltusrol in New Jersey, carded an even-par 72 at Druid Hills.
Seventeen-year-old high school junior Ty Tryon, who indicated last week that he would turn pro after the U.S. Amateur, recorded a pair of double-bogeys on East Lake's front nine Monday en route to a 10-over-par 80.
'It was just a tough day,' Tryon said. 'If I missed a shot, I got burned for it, and if I hit a good shot, I didn't get anything for it.'
Tryon became the youngest golfer in 44 years to make the cut in a PGA Tour event after he Monday qualified for the Honda Classic in March. Only 16 at the time, he finished the event in a tie for 39th.
He also played in last month's B.C. Open on a sponsor's exemption, shooting a65 three days and wound up tied for 37th.
First Round Results
(e-East Lake, d-Druid Hills):
Robert Godfrey,Clemson, S.C., 30-33--63e
Lucas Glover,Greenville, S.C., 32-32--64d
James Driscoll,Brookline, Mass., 31-33--64e
Ben Portie,Westminster, Colo., 35-31--66d
Chris Wisler,Dover, Del., 34-32--66d
Graeme McDowell,Northern Ireland,, 33-33--66d
Chez Reavie,Mesa, Ariz., 34-33--67d
Dave Womack,McDonough, Ga., 32-35--67d
Robert Hamilton,Carmichael, Calif., 32-35--67e
Oliver Wilson,England,, 35-33--68d
Daniel Summerhays,Farmington, Utah, 33-35--68d
Richard McEvoy,England,, 33-35--68d
Camilo Villegas,Colombia,, 33-35--68d
Kyle Coody,Plano, Tex., 36-32--68e
Brad Morris,Clay City, Ky., 34-34--68e
Jerry Courville,Milford, Conn., 32-36--68e
Scott Feaster,Columbia, S.C., 34-35--69d
Scott Wingfield,Las Vegas, Nev., 33-36--69d
Paul Simson,Raleigh, N.C., 36-33--69d
Matt Bettencourt,Modesto, Calif., 33-36--69d
Nicholas Thompson,Coral Springs, Fla., 34-35--69d
Brandon Daum,USAF Academy, Colo., 31-38--69d
Bubba Dickerson,Hilliard, Fla, 35-34--69e
Craig Steinberg,Los Angeles, Calif., 31-38--69e
Nick Watney,Fresno, Calif., 34-35--69e
Brooks Kelly,Sierra Vista, Ariz., 35-34--69e
Michael Sims,Bermuda,, 34-35--69e
Brock Mackenzie,Yakima, Wash., 35-34--69e
D.J. Trahan,Inman, S.C., 33-36--69e
Chan Wongluekiet,Bradenton, Fla., 35-35--70d
Kevin Na,Diamond Bar, Calif., 37-34--71d
Jeff Quinney,Eugene, Ore., 35-37--72d
Nick Cassini,Athens, Ga., 36-37--73d
Trip Kuehne,Dallas, Texas, 38-36--74e
Erik Compton,Miami, Fla., 37-38--75d
David Eger,Ponte Vedra Beach, Fla., 35-42--77e
Ty Tryon,Orlando, Fla., 43-37--80e