American veteran Phil Mickelson openly questioned the methods of his captain Tom Watson after Europe retained the Ryder Cup at Gleneagles.
The US lost 16½-11½, their eighth defeat in the last 10 Ryder Cups.
With Watson sitting nearby at the news conference, Mickelson heaped praise on 2008 captain Paul Azinger, the last captain to guide the US to victory.
Watson said: "He has a difference of opinion. That's OK. My management philosophy is different than his."
But former Europe captain Nick Faldo said Mickelson had "thrown his captain right under the bus".
Mickelson, who was making a record 10th Ryder Cup appearance at Gleneagles, was said to be unhappy at being left out by Watson on Saturday.
And the 44-year-old, who won two out of a possible three points, said Watson had "strayed from a winning formula".
"There were two things that allowed us to play our best that Paul Azinger did," said Mickelson, a five-time major winner.
"First, he got everybody invested in the process. He got everybody invested in who they were going to play with, who the picks were going to be, who was going to be in their 'pod', when they would play, and they had a great leader for each pod. We hung out together.
"The other thing that Paul did really well was he had a great game-plan for us - how we were going to go about doing this, how we were going to go about playing together, if so-and-so is playing well, if so-and-so is not playing well.
"Those two things helped us bring out our best golf. We use that same process in the Presidents Cup [US versus the rest of the world] and we do really well.
"Unfortunately we have strayed from a winning formula for the last three Ryder Cups and we need to consider maybe getting back to that formula that helped us play our best."
Mickelson added that neither he nor any of the other American players had been consulted in any of the decision-making.
Asked if he thought his comments were disloyal to Watson, Mickelson said. "I'm sorry you're taking it that way. I'm just talking about what Paul Azinger did to help us play our best."
But Faldo, under whose stewardship Europe lost to Azinger's team in 2008, criticised Mickelson on the Golf Channel.
"That should have been a private conversation," he said. "Phil certainly doesn't respect Tom Watson."
Colin Montgomerie, winning captain in 2010, agreed that Mickelson's comments were inappropriate.
"Should we go into this one hour after we've been defeated? The answer is a flat no," said Montgomerie.
"You support your captain under all circumstances. In public, you respect and honour your captain."
Watson 65, has conceded he made errors of judgement over the three days, such as not playing in-form rookies Patrick Reed and Jordan Spieth on Friday afternoon.
But the eight-time major winner, who was the last American skipper to win in Europe in 1993, said he had not read Azinger's book on Ryder Cup strategy.
"I didn't discount it. I just had a different philosophy right off the bat," he said.
"My two jobs are to make the captain's picks and then put the team together. The bottom line is the Europeans kicked our butts. They were better players this week."
Jim Furyk, making his ninth Ryder Cup appearance, was reluctant to get involved in the debate and admitted he had never really analysed why they could not get it right.
"I've known Phil my entire life and I have a lot of respect for our captain. I know he put his heart and soul into it for two years," Furyk said.
"We all came here to try to win a Ryder Cup together. We've fallen short quite a bit. If I could put my finger on it, I would have changed things a long time ago, but we are going to keep searching."