Ricardo Clark admitted responsibility after his side's 2-1 defeat to Ghana in the last 16 of the World Cup on Saturday.
The United States midfielder was caught in possession after five minutes, allowing Kevin-Prince Boateng to run through and drive past Tim Howard to open the scoring.
With Ghana's passing superb in the opening stages, and the USA in danger of being outplayed, Clark was booked for a crude foul on Boateng. His miserable night ended when he was withdrawn after 30 minutes for Maurice Edu.
Clark was clearly disappointed, and US coach Bob Bradley made a point of hugging him on the touchline and explaining his decision.
"He just said he took me off because I had a yellow and if I got another one I'd get sent off," Clark explained. "It wasn't the best performance from me. I had some good moments, but unfortunately one of my bad moments led to a goal on the counterattack. A player of my calibre and experience shouldn't be making those mistakes."
The Eintracht Frankfurt midfielder received the ball on halfway, but seemed to stumble, gifting possession to Ghana's Kwadwo Asamoah, who helped the ball on to Boateng.
"I kind of got the ball stuck in my feet," he said. "I think they played [the ball on] in the midfield. I got caught in my decision making, didn't react fast enough and the guy stole the ball. Unfortunately it led to the goal. I feel like I let my team down. I take full responsibility on the goal. I apologised for the goal (to the coach)."
Even a few minutes after the game, as Clark admitted culpability, it seemed it was an incident that he would play over and over in his mind, something that will haunt him. He admitted that what made it all the worse was that he hadn't been able to stay on to try to rectify the mistake.
"Of course I wanted to stay on," he said. "But it's up to the coach."
The introduction of Edu seemed to tip the game in the USA's favour, particularly after the introduction of Benny Feilharber at half-time allowed Clint Dempsey to move into a more central position.
It was Dempsey who won a penalty after 61 minutes, beating John Mensah and then being tripped by Jonathan Mensah. Landon Donovan scored from the spot.
"I did think we'd win after the penalty-kick," Clark said."We were applying the pressure and could have had two or three goals but it didn't happen. Ghana are a good team. They wouldn't have made it this far if they were not."
Jonathan Mensah similarly thought the game was slipping away from Ghana when Donovan equalised. "When they came up 1-1, we had to make sure we weren't down, we had to fight to get another goal and we did," he said.
"When the game was over 90 minutes we knew we had to pick ourselves up and fight and that's what we did. We talked to each other in the group, got together and that was what gave us the spirit and strength."
Asamoah Gyan thumped the winner three minutes into extra time. Mensah insisted that his side don't fear Uruguay, who stand between them and being the first African team to reach a World Cup semi-final.
"All the other African teams are out so the whole of Africa is looking at us. So we need to deliver.
"We're not worried about Uruguay. When we qualified to play the USA we weren't worried and we won, so we're going to do the same thing."