Michael Bradley held a one stroke lead over a group including Fredrik Jacobson after a first day of the Travelers Championship on which only just over three-and-a-half hours' play was possible due to thunderstorms.
Bradley recorded seven birdies and a bogey in his 16 holes in sodden conditions before storms forced the players off the course at 1130 local time (1530 BST).
They never returned and play was suspended just after 6pm (2200 BST), with only six players having completed their first rounds.
"The course is unplayable," Bradley said. "There's a lot of water on the course. It's going to be a little wet [Friday] but it's two holes and I'm done."
Fiji's Vijay Singh, Swede Jacobson and Andres Romero of Argentina are alongside American quartet Chris Couch, Bryce Molder, John Rollins and Bo van Pelt in the group one shot back at five under, with a further seven home players including Zach Johnson, Nick Watney and Ben Crane at four under.
Kris Blanks' two under par 68 was the best of the handful of completed rounds.
