The details of the bust-up between Roger Federer and Stan Wawrinka at the Barclays ATP World Tour Finals on Saturday night became clearer yesterday as well-placed sources attested that the two men found themselves "thrashing out their differences" in the O2 Arena's gym in London after their semi-final.
Furthermore, the common thread in the accounts of a hot-tempered match concerns the role of Federer's wife, Mirka.
Mirka's intense and even provocative support for her husband - which peaked just before Wawrinka served for the match at 5-4 in the third set - caused Wawrinka to complain about her behaviour.
In those late stages, Mirka is understood to have challenged Wawrinka directly, accusing him of whingeing. Wawrinka failed to convert four match points - three of them in that critical service game at 5-4 - before Federer finally came through 4-6, 7-5, 7-6.
When he came into the interview room Wawrinka was asked: "At some point late in the third you seemed upset with someone speaking before points. Can you explain what happened?" His response was cryptic: "Not much. Nothing special. Tense match. It's never easy."
Information has now come to light about the aftermath of the match, when Federer and Wawrinka were encouraged by senior tennis figures to put the issue to bed at once. The two men conducted a heated 10-minute debate in the O2 Arena's gym, in which Federer was understood to be the more assertive party.
The tension was not fully resolved but they have agreed to concentrate on their shared goal of defeating France in the Davis Cup final, which starts in Lille on Friday. Some even believe that Wawrinka may be inspired by his lingering frustration.
"The Swiss guys might have a little more steam when they are playing doubles, a little more fire," one well-known former player said.
At the same time, though, the Swiss captain, Severin Luthi, must be wondering what has hit him after a potentially crippling weekend for team unity. There is also a question over whether the fallout contributed to Federer's back trouble, which he says developed in the third set tiebreak and eventually led him to make a dramatic and unprecedented withdrawal from the final on Sunday at the 11th hour.
At the very least, the gym summit held him up from attending to the injury with physiotherapy at the earliest opportunity.
John McEnroe, commentating on ESPN, alluded to the issue when he said: "There was a long talk between the players that extended late into the night. And the stress of that, I can't confirm all of this, but a lot of this went on and that caused ...
"I don't think that helped the situation."
Wawrinka and Federer have long had a genuinely close relationship, though it must be said that Wawrinka was never a threat to Federer's primacy in Switzerland until this year. (© Daily Telegraph, London)