Seamus Power and Graeme McDowell were under par but well down the field when the Puerto Rico Open was suspended because of heavy rain.
Newlywed Trey Mullinax shot a nine-under 63 to set the clubhouse and lead by one from D.A. Point, who holed out from the fairway for an eagle two on his final hole for a 64 at Coco Beach Golf & Country Club.
Power was tied 55th at two-under par after 13 holes having mixed three birdies with a solitary bogey at the 12th, his third.
McDowell was tied 71st at one-under par with just the ninth hole to play to complete his round when the course became too wet to continue play. Scores
Mullinax made nine birdies and saved par from 15 feet at the last to open with a 63 just five days after getting married.
He was coming off consecutive missed cuts in Florida when he got married Saturday to Abi Essman, whom he has dated since high school. Several of his Alabama teammates were at the wedding in Birmingham, Alabama, including Justin Thomas.
"Obviously, to shoot the score I shot today you have to putt well," Mullinax said. "
But it was nice to hit the ball like I feel I've been playing. I feel like I've been hitting the ball well, just haven't been scoring. But today I hit the ball nice, and it was a good result."
Points finished his round of 64 with a nine-iron that he holed from the ninth fairway for an eagle.
"Today was the calmest day I've ever seen here, so it was pretty much a perfect nine-iron," he said. "I knew I had a little backstop and I could hit it as hard as I want, and I threw it 149 yards and it spun back and went right in."
The Puerto Rico Open is opposite the World Golf Championships event in Texas this week, meaning a winner does not earn an automatic spot in the Masters.
Wesley Bryan, who opened with a 63, would need to win to have any chance of moving into the top 50 in the world ranking and qualifying for Augusta National.