Three-time major winner Jordan Spieth took the blame after he and Ryan Palmer missed the cut by one stroke at the Zurich Classic of New Orleans.
Spieth, 24, found the water on the final two holes as a two-over-par 74 left them four over after two rounds of the two-man team event.
Fellow Americans Michael Kim and Andrew Putnam, who went round in 69, lead by one shot on 13 under at TPC Louisiana.
“I cost our team an opportunity, which really sucks,” Spieth said.
“It’s not a good feeling. It’s much worse than if it’s just you.”
England’s Chris Paisley shot a hole-in-one at the third but he and Tommy Fleetwood, who were two shots off the lead after the first round, slipped to joint 19th on seven under thanks to a 75.
Americans Kevin Kisner and Scott Brown are one shot behind Kim and Putnam in second place.