LAS VEGAS -- Tom Byrum, who began the week in danger of losing his PGA Tour card, shot his third straight 65 under ideal conditions Friday to take a two-shot lead in the Invensys Classic at Las Vegas.
Billy Andrade set the course record at Southern Highlands with a 9-under 63.
On another day when par seemed merely an abstract thought on the three desert courses pros shared with amateur partners, Byrum finished with five straight birdies to lead Billy Andrade with two rounds still to play in the 90-hole tournament.
"I don't have an explanation for it, but I'll take it," Byrum said.
Byrum, a stroke ahead of Blaine McCallister to start the day, played before only a handful of people at one of two satellite courses used in the tournament and didn't see a leaderboard all day.
When he was finished, though, he was on top of the board at 21-under. And he has no plans to change his strategy for the weekend.
"My mentality will be to not look at any scores and try to birdie every hole I play," Byrum said.
Andrade was at 19-under after a 63, which was matched by Mike Weir as the low round of the day. Weir was another shot back at 18-under, followed by Scott McCarron and McCallister at 17-under.
Casey Martin remained in contention at 15-under, six shots back, as did Phil Mickelson, who is using the tournament as a warmup for next week's Presidents Cup.
"You feel like if you don't shoot 8- or 9-under, you're giving one back," Mickelson said after shooting a 67 at TPC Summerlin, where both weekend rounds will be played.
Byrum, who came to Las Vegas on the bubble for making the top 125 and retaining his PGA Tour card, played like tour survival was the last thing on his mind.
Byrum is 125th on the money list with $330,583, a position he must hold if he is to be exempt for next year.
"I wish we had started the season in June," said Byrum, who says he plays better in the summer and fall. "I'd never be on the bubble then."
Byrum seemed in danger of losing his lead before hitting three straight wedges to within 4 feet of the hole and making the putts on his back nine at Southern Highlands Golf Club. He followed it with a 10-footer on the next hole, and a flop shot within 6 feet for his final birdie on the last hole.
"Never," Byrum said when asked the last time he had three straight 65s.
Andrade, meanwhile, put himself into contention as he also tried to cash in the $4.25 million tournament to keep his card.
Andrade is 159th on the money list and needs a big finish to put himself in position to keep his card.
"My standing on the money list sucks," Andrade said. "I have to put it in gear this next month."
Andrade, who has won three times in 14 years on the tour, was in a similar position three years ago when the tournament was known as the Las Vegas Invitational. Instead of needing a big finish to retain his tour card, though, he was looking to make enough money to get into the top 30 and make the lucrative season-ending Tour Championship.
He ended up falling $5 short.
"Maybe Las Vegas owes me one," Andrade said. "Maybe I can take care of business, come here and win, and it will erase the bad memories of not getting in the Tour Championship."
Andrade wasn't particularly effective with his irons but made plenty of putts at Southern Highlands, a new course that has been particularly receptive to scoring. His 63 set the course record.
"You just got to keep making a lot of birdies," he said. "Everybody knows that is the mindset coming into Las Vegas."
Divots
Rocco Mediate had a hole-in-one at the Desert Inn Country Club, hitting a 4-iron 212 yards on the 11th hole.
McCarron feels at home in Nevada, where he has relatives in Reno and Las Vegas. It showed both here and at the Reno-Tahoe Open in August, where he finished fourth.
Martin figures he needs to make some $250,000 in his last three tournaments to gain a tour
exemption for next year.
Robert Gamez, a Las Vegas native who has a home on the third hole at TPC Summerlin, is 12-under as he tries to improve on his 145th position on the money list.