At 21-under-par, Byrum is two shots clear of Bilyl Andrade. Mike Weir is three back at 18-under, while Scott McCarron and Blaine McCallister share 4th place at 17-under-par.
Byrum's Friday 65 didn't come easy. Playing Southern Highlands, Byrum began on the back nine and made the turn in 2-under-par 34. But after four consecutive pars to start his inward half, Byrum strung together five successive birdies to end the day.
'I got hot at the end and just ran out of holes,' Byrum joked.
Byrum's sterling play is a bit of a surprise, even to him. Since tying for 7th at the Reno-Tahoe Open in late August, the 14-year PGA Tour veteran has missed three cuts in his last five starts. In the process, Byrum has dropped to the precarious position of 125th in yearly earnings. The top 125 by season's end earn their 2001 Tour playing privileges.
'I'd been struggling a bit,' said Byrum, whose first and only Tour victory came at the 1989 Kemper Open. 'I hadn't been playing that well. I just needed to get on a roll early and get it going.'
'Roll' is an appropriate word for Byrum this week. Through three rounds, he leads the tournament in putting - averaging just 26 putts per round. That's an impressive number for two reasons; the first being that the Invensys Classic is contested over three different courses - Southern Highlands, Desert Inn and the host course, the TPC at Summerlin. Byrum's also been struggling with the flatstick all year. Entering this week, Byrum ranked 148th on Tour in putts per round, averaging over 29 strokes every 18 holes played.
Putting hasn't been a problem for Andrade in 2000, nor has it been this week. Andrade ranks second, behind Byrum, in putts per round in Las Vegas. Still, it's a crapshoot as to whether he will finish the season inside the top 125 in earnings.
The two-time Tour winner stands in 159th position on the money list. His last victory, the 1998 Bell Canadian Open, insured his playing status for this season, but he'll have to work to maintain it in 2001.
Friday, Andrade made great strides in securing his 2001 Tour card by firing a 9-under-par 63 at Southern Highlands. Like Byrum, Andrade started the day on the 10th; and just like the man he's chasing, Andrade finished strongly by birdying five of his final seven holes.
The 36-year-old Andrade has a bit of history at this event. Three years ago, he missed a 15-foot putt on the 72nd hole that would have earned him spot in the season-ending Tour Championship. Instead, he missed qualifying for the $4-million event by a mere five dollars.
'Maybe Las Vegas owes me one,' Andrade said. 'I played very well in 1997, but not a lot of good finishes since. Back then, I was on the top-30 bubble, this year it's just the opposite.'
Last season, Andrade finished 118th on the money list. It was his lowest finish since his rookie season in 1988. In fact, `88 was the last time Andrade made the dreadful trip to Q-School.
Weir matched Andrade's course-record at Southern Highlands on Friday. The Canadian, who will compete for the International squad at next week's Presidents Cup, fired a front-nine 6-under-par 30, and then added three more birdies on the inward half for a bogey-free 63.
Like Andrade, McCarron has a story involving Q-School and the Invensys Classic. But unlike his peer, McCarron's story had a happy ending. In his rookie season of 1995, McCarron tied for third at the former Las Vegas Invitational to secure his sophomore playing privilege.
McCarron is looking for a duplicate in 2000. The two-time Tour winner is currently 123rd on the money list.