Slocum, a two-time winner this year, was at 1-under for his day following the first nine holes, but then made birdie at the tenth, eagle at the par-4 11th, and two more birdies at Nos. 15 and 17 to finish at 16-under-par 200.
Not far behind Slocum is Scott Peterson, who shot 67 for the day to finish one back at 15-under, while Rod Pampling is a stroke further removed after a Saturday 69.
The round of the day, however, came by Iain Steel, a native of Malaysia.
Steel blazed The Champions Club Saturday in 10-under-par 62 to finish at 13-under for the tournament, just three off the pace.
His day began with an eagle at the par-5 2nd, and he followed it up with four more birdies on the opening nine holes. Another eagle at the par-5 10th set up additional birdies at Nos. 14 and 17 for the sparkling 62.
The 30-year-old is playing in just his second Buy.Com event of the year. He missed the cut earlier in the season at the Steamtown Classic, and he made only five cuts in 19 events last year on the tour.
Full-field scores from the Buy.Com Omaha Classic