"I wasn't patient, and that was the issue," he said. "Bad bounces are going to happen out here, but I could have shot three shots lower without even playing any different."
Despite being 6-over for the tournament, Spieth enjoyed himself, in part because he played alongside Northern Irishman and major winner Darren Clarke.
"He's obviously loved, and I can see why. Extremely nice guy, he's very selfless, he's rooting for me. It was cool," Spieth said.
Despite a full schedule since March and the pressures of being in contention the previous three weekends, Spieth said he didn't think fatigue was a factor in his performance here. That said, he wasn't unhappy about taking time off after the Open.
"Yeah," Spieth acknowledged, "I'm looking forward to it."