Shiegki Maruyama and Fredrik Jacobsen were thrilled to take advantage.
Maruyama eagled the par-5 16th to get into a three-way tie for the lead, Jacobsen moved steadily up the leaderboard all day, and Chopra simply unraveled on the back nine Sunday at the Ginn sur Mer Classic -- setting the stage for a potentially wild finish Monday morning at Tesoro Club.
Play was suspended for the day by darkness with Maruyama, Jacobsen and Chopra all at 18 under, two shots ahead of clubhouse leader Dicky Pride.
Chopra had a four-shot lead when he made the turn Sunday afternoon, having just tapped in a 2-footer for a birdie that pushed him to 20 under. But two bogeys in his first four holes on the back side gave his closest pursuers a chance.
The final round will resume at 8 a.m. Monday, with $810,000 going to the winner.