Villegas stands at 16-under-par 200 for a two-stroke lead heading into the final round at Midland Country Club.
Kris Cox shot a 68 to remain tied for second place at 14-under-par 202, where he was joined by Garrett Willis, who shot a 67 in his third round. Scott Gump (67) and Craig Bowden (69) share fourth place, one stroke further back.
Chris Tidland is alone in sixth place at minus-12 after firing a 6-under 66 in his third round. Six players are tied for seventh place one stroke further back.
The tournament is finally back on track following a four-hour weather delay on Thursday that forced the completion of the second round back to Saturday morning.
That one delay has meant two straight marathon days for some players.
Villegas, for one, endured 33 holes on Friday after play was suspended just three holes into his first round. But he weathered the long day impressively with 15 birdies in the 33 holes, and even carded a bogey-free second round.
The 23-year-old Colombian ended up with a two-shot advantage when the second round was completed Saturday morning -- and he made sure the lead stood, even though he preferred his long Friday to the windy conditions Saturday.
'I think it was harder today than other days,' said Villegas, who has yet to win in his rookie season on the Nationwide Tour. 'There was more wind today, but the greens are so good and guys out here are going to make putts.'
Villegas maintained his frontrunner status with birdies on two of his first four holes, both par-5s . He rolled in a birdie putt at the par-3 eighth, but then dropped a stroke at the ninth to make the turn at 14 under.
But that would be the final miscue of the day for Villegas, who cruised through the back nine with a pair of birdies and seven pars.
Part of the reason for Villegas' steady third round was his club selection. He used a 2-iron on eight of the 10 par-4s, and ended up hitting eight of 14 fairways.
'That 2-iron, that's my baby,' said Villegas.
'You've got to put it in play out here. There is no need to start throwing it off line and giving shots away.'
If he doesn't give away his lead, Villegas would win his first title after beginning the year with no status on the Nationwide T best-ever placement was a tie for second place at the first tour stop this year, the BellSouth Panama Championship in January.