Jurgen Klinsmann called Jozy Altidore's red card "unfortunate" but said he was not concerned by a trend of the United States giving away second-half leads after a 1-1 draw in Switzerland on Tuesday.
The U.S. led 1-0 on Brek Shea's goal from a free kick on the stroke of halftime, but the momentum shifted in the 68th minute when Altidore was booked for tripping up Francois Moubandje.
Altidore then turned to speak angrily toward Italian referee Luca Banti, who immediately sent off the U.S. striker with a straight red card.
U.S. midfielder Alejandro Bedoya said he believed the referee warned Altidore at halftime about his cursing, and Klinsmann, who played in Italy for four seasons, said he told his players to use caution with the Italian official as well.
"He used some verbal words," Klinsmann said of Altidore's dismissal. "I asked the ref, obviously -- I told the players at halftime: 'Guys you can probably do fouls, you can do certain things but never joke with an Italian referee.'
"It's unfortunate but it happened. He got sent off for a verbal comment by an Italian referee."
Altidore said he was sorry for his actions in a statement issued through the U.S. Soccer Federation.
"I want to apologize to our fans and my teammates," Altidore said. "Emotion got the best of me and I put our team in a tough position. That's not the type of role model I want to be. All credit to the boys for grinding it out and earning a positive result."
The U.S. have now been outscored 12-1 in the second half of matches since the World Cup.
"It might be a theme, but it's not a problem because we know the reasons why certain things happen," Klinsmann said of the Yanks' second-half woes. "Maybe some games we kind of ran out of gas earlier and then made individual mistakes.
"This was a mistake that had nothing to do with their physical condition, which is good. I think we're making progress. We're going to get closer to the 90 minutes that we were playing in the World Cup, so this is good to see and the players too have willingness to take the game to their opponent and go all the way to the end. So even if it happened in the 80th minute as well today, we're through with that. It's not a concern at all."
Aside from Altidore's moment of madness, Klinsmann was satisfied with what he saw as good preparation for this summer's Gold Cup.
"The game I think was an interesting game," he said. "I think we had enough chances in the first half to put the game away. Unfortunately, we didn't do that. [Shea's goal] was a beautiful free kick but we should have scored before that.
"From our point of view, obviously with the red card it changed. Missing Jozy up front, who is a danger, who is a threat, and so it got more and more difficult. But overall, I saw a lot of good stuff overall from players, from the entire group.
"They grinded it out, they wanted a result really badly, and it was enjoyable on the bench to feel that and see that, that everybody was doing something to get a result against a very good team. I think they did fine picking up a rhythm in the first half, starting to combine and having a flow in their passing and the whole movement.
Klinsmann highlighted the Yanks' defensive effort, which limited Switzerland star Xherdan Shaqiri's freedom.
"Defensively, I think they did a wonderful job shifting, always doubling the side, especially Shaqiri," Klinsmann said. "When you give him too much space he can hurt you badly within a second. So we closed him down, made sure that he doesn't have the circulation he usually has. Tactically, it was very good work."
At the other end, however, Klinsmann said he would have liked to have seen more clinical finishing, as Michael Bradley missed an easy chance to score in the first half when the ball fell to him in the box.
"Obviously when you create chances and you end up three, four times in front of their goalkeeper, you want to put that thing in," Klinsmann said. "That was the part that we were missing. But there were some combinations that were really fun to see. The movement off the ball, which we really tried to focus on in training as well. That was all right."
Switzerland eventually equalized following a corner when Valentin Stocker tapped in from close range.
"It was a little bit of a hectic moment there. It was not cleared," Klinsmann said. "I think Timmy Chandler claimed offside but he was the one that kept everybody on. From a set piece, always there's a danger. But it was nice to see that then they kept the energy, they kept the enthusiasm going and they badly wanted a result.
"We wanted to make sure we didn't give this game away as well. So overall it was a very good team performance."
Information from ESPN FC'S Doug McIntyre was used in this report.