Chattanooga, TN (My Sportsbook) - David McKenzie, Todd Demsey and Geoffrey Sisk all opened with eight-under 64s Thursday and stand atop the leaderboard with the first round of the Chattanooga Classic suspended due to darkness.

All three players are outside the top 25 on the money list. If they reach that mark, they would earn their PGA Tour card for next season. There is one more event before the season-ending Tour Championship which takes the top 60 on the money list. Only McKenzie is inside the top 60 entering this week.

Tyrone Van Aswegen, who tied for third last week, opened with a seven-under 65 and is alone in fourth at the Black Creek Club. Six more golfers, including former PGA Tour players Ian Leggatt and Guy Boros, share fifth at minus-six.

There were nine players left on the course when play was suspended for the night. The first round will resume at 8:00 a.m. (et) Friday, while the second round will start as scheduled at 7:50 a.m.

McKenzie, who was in the first group out in the afternoon, played the back nine first and got off to flying start. After a par on the 10th, he birdied five of the next six holes. A birdie on the par-five 18th helped McKenzie turn in minus-six, which gave him a share of the lead at the time.

On the front nine, McKenzie tripped to a bogey on the par-five fourth. He came back with three straight birdies from the sixth to jump to eight-under. McKenzie parred the last to get into the clubhouse first.

Demsey, playing two groups behind McKenzie, birdied four of five holes from the 11th. He converted back-to-back birdie chances at 18 and one.

With birdies on four, six and eight, Demsey was the first player to reach minus-nine for the event. However, he faltered to a bogey on the ninth, his last, to finish at eight-under.

Sisk started on the front nine. He birdied back-to-back holes from the second and again from the fourth. After three straight pars, he birdied the 10th and came back with a birdie on No. 14 to get within two of the lead.

The 44-year-old made birdie efforts on 14 and 15 to gain a share of the lead. Sisk could have taken the lead by himself, but parred the final three holes to create the three-way tie for the lead.

Roberto Castro was six-under through 16 and closest to the lead when play ended for the day. He was tied for fifth with Leggatt, Boros, Brian Vranesh, Dustin Bray and Chris Baryla. Six more players are one back at five-under 67.