Jamie Lovemark and Jhonattan Vegas shared the Zurich Classic lead at 11 under Friday when second-round play was suspended because of darkness.
Lovemark had a 27-hole day at hot and humid TPC Louisiana, completing a 5-under 67 in the first round and adding a 66 in the second in the event that fell behind schedule Thursday with a long rain delay.
Vegas, from Venezuela, shot 64-69. He played 31 holes.
None of the players in the afternoon wave finished the round.
Brian Stuard, the overnight leader after a 64 on Thursday, was 10 under with six holes left.
Top-ranked Jason Day was 5 under with eight holes left. The Australian is the first No. 1 player to play in the event since David Duval in 1999.