The repercussions of another Ryder Cup defeat for the United States have already begun, with senior professional Phil Mickelson openly questioning the captaincy of Tom Watson.

America's 16 1/2-11 1/2 defeat at Gleneagles was their eighth in 10 events and apparent discontent within the camp surfaced at their team press conference afterwards.

A number of PGA Tour professionals not with the team this week have already called for Paul Azinger, who masterminded their last victory in 2008, to be brought back as captain, and there already seems to be some support for that - or at least his methods of a 'pod system' - within the team itself.

"There were two things that allowed us to play our best that Paul Azinger did: one was he got everybody invested in the process," said Mickelson, making a record 10th appearance for the US and who was understood to be unhappy at having to sit out the whole day on Saturday for the first time in his career.

"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 and we were all invested in each other's play. We were invested in picking Hunter (Mahan) that week, we were invested in the process.

"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 - we had a real game plan.

"Those two things helped us bring out our best golf. We use that same process in the Presidents Cup and we do really well.

"Unfortunately we have strayed from a winning formula in 2008 for the last three Ryder Cups and we need to consider maybe getting back to that formula that helped us play our best."

Mickelson was asked whether he thought his comments were disloyal to Watson.

"Oh, I'm sorry you're taking it that way. I'm just talking about what Paul Azinger did to help us play our best," was the response.

"You asked me what I thought we should do to bring our best golf out and I'd go back to when we played our best golf and try to replicate that formula."

Asked whether he was consulted in any of the decision-making Mickelson added: "No, nobody here was in any decision."

Watson 65, made some significant errors of judgement over the three days - like not playing in-form rookies Patrick Reed and Jordan Spieth and not sending out Mickelson and Keegan Bradley to resume their successful partnership on Saturday - but he stood by his decision and brushed aside Mickelson's comments.

"He has a difference of opinion. That's okay. My management philosophy is different than his," he said.

Watson said he had not read Azinger's book about a winning Ryder Cup strategy.

"I didn't discount it. I just had a different philosophy right off the bat," he said.

"I felt that the assessment of the players was paramount from the standpoint of my vice-captains and me to see who was going to play with whom.

"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."

America's other senior player Jim Furyk, on his ninth appearance, was reluctant to get involved in the debate on captaincy strategy 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 in it for two years," Furyk said.

"I don't think it's wise for either one of us to be pitted in the middle of that.

"We all came here to try to win a Ryder Cup together. We've fallen short quite a bit.

"Five of you have already asked me tonight what's the winning formula and what's the difference year-in, year-out.

"If I could put my finger on it, I would have changed this s*** a long time ago, but we haven't and we are going to keep searching."