Vegas is tied with American Jamie Lovemark at 11-under as the second round of the USPGA Tour event was suspended because of darkness.
All of the afternoon starters were still on the course when play was stopped for the evening. They will return to complete the second round on Saturday morning before starting the third round.
Lovemark carded a six-under-par 66 in the second round after finishing the final nine holes of the first round in the morning for a 36-hole score of 133 at TPC Louisiana.
Vegas played 31 holes and added a 69 to his opening-round 64. He overcame a double-bogey seven on his second hole with five birdies.
Lovemark, who has yet to win on the USPGA Tour, had just one bogey and six birdies in his round. Through two rounds, he has played the four par fives on the course in seven under.
First-round co-leader Brian Stuard was one shot back at 10 under with six holes remaining. Harold Varner completed a 67 and was at eight-under 136.
World number one Jason Day, of Australia, was at five under with eight holes remaining.