"It was rare to match up a ball-striking day and make everything. It happened today," Bradley said. "The hole looked huge. Even the putts I missed almost went in."
The 60, with 10 birdies and an eagle 3 at the 542-yard seventh, gave Bradley a three-stroke lead over 2011 Masters champion Charl Schwartzel among those who played morning rounds.
Robert Karlsson, Harris English and Ted Potter jnr all had 64s in the morning rounds, which came after 38mm of rain fell on the course overnight from a storm system that spawned 10 tornadoes and killed at least six people in North Texas. There was no significant damage to the course, where players were able to lift, clean and place golf balls in fairways.
"Seems like you don't get many of those opportunities, so being out here first was a bit of an advantage," said Schwartzel, who hit all 18 greens in regulation. "So much rain, it softened up. Played long off the tee, but it's a big advantage going into the greens with the second shot. You could attack flags."
Arron Oberholser shot 60 in the second round of the 2006 Nelson on the Cottonwood Valley course across the street that used to be used in the first two rounds. Sam Snead shot 60 in the 1957 tournament at Glen Lakes Country Club, which at the time tied the PGA Tour record.
Five players have shot 59 in official PGA Tour events. Al Geiberger had the first in the 1977 Memphis Classic, while Paul Goydos and Stuart Appleby had the last three years ago. Ryo Ishikawa had the lowest round on a major tour, shooting a 12-under 58 on the Japan Tour in 2010.
Bradley, the nephew of LPGA Tour great Pat Bradley (31 victories with six majors), got his first PGA Tour victory when he won a one-hole playoff with Ryan Palmer at the Nelson two years ago. Bradley has four consecutive top-10 finishes earlier this season, but missed the cuts in his last two tournaments.
Palmer's opening 65 came two days after attending the funeral of one of his best friends, who was killed in a car accident last week. Palmer found out about Clay Aderholt's accident while at the Players Championship, where with a heavy heart and his friend's initials on his cap he tied for fifth.
"Trying to get back in the swing of things," said Palmer, who lives in nearby Colleyville. "Being at home is nice, my own bed, so that made it easier when I got back [from the funeral] Tuesday night."
Palmer gave the white cap that he wore on Monday (NZT) to Aderholt's wife and signed it to his 4-year-old son. He gave a black cap with the initials to his late friend's father. "We will always remember him and maybe we can honour him even more on Sunday afternoon," Palmer said.
Defending Nelson champion Jason Dufner shot a 70 in a group with good friends Bradley and Matt Kuchar (69).
AP