The prime minister was back in parliament again on Monday - her fourth appearance in six days - to update MPs on her 28,000 mile round trip to the G20 summit in Argentina.
She talked up the prospects of post-Brexit trade deals with Japan, Canada, Argentina and Australia, as she banged the drum for global Britain.
But the real Brexit battle was fought for her by the government's top legal brain - Geoffrey Cox.
With just seven days left to try to turn the overwhelming opposition for her Brexit deal around, the prime minister deployed her attorney general - an ardent Eurosceptic - to the dispatch box to try to sell her deal.
He was there, ostensibly, to explain why the government has - despite a motion laid by MPs - decided not to publish his full legal advice on the Brexit deal, releasing a summary instead.
But he was also there not just to defend the prime minister, but to try and sell her deal to recalcitrant Conservative MPs by attempting to reassure them that her Brexit compromise - despite having "unattractive, unsatisfying elements" - was not going to trap the UK into a customs union with the EU forevermore.
"I make no bones about it - I would have preferred to have seen a unilateral right of termination in this backstop," he told the Commons in his sonorous voice.
"But I'm prepared to lend my support to this agreement because I do not believe that we're likely to be entrapped in it permanently."
Sky sources have been told that Mr Cox's legal advice concludes that the European Court of Justice would not in practice force the UK to stay in the backstop against its will if a case was brought by the government.
But he is not publishing that advice because ministers have consistently argued legal government advice is privileged in the same way as any given by a lawyer to a client, and it is a confidentiality that the government requires to function.
He said: "In this case I am convinced that in order to disclose any advice that might have been given would be fundamentally contrary to the interests of this country."
But the Commons is not satisfied with a summary of the advice - they want the full legal advice to be published.
Mr Cox might be one of the country's most accomplished barristers, but he failed to convince sceptical MPs there was no public interest in publishing the government's full legal advice.
Six opposition parties - including the DUP - teamed up on Monday night to ask the Speaker John Bercow to start contempt proceedings against ministers for withholding Brexit legal advice.
This is an extraordinary development, but these proceedings will pale into insignificance next week should Mrs May lose the meaningful vote.
At that point, she could face a no confidence vote in the Commons and a confidence vote from her own MPs.
This is a far greater concern for No 10 than sanctioning of the government or a minister for contempt, which helps explain why the prime minister has deployed leading Brexiteers Mr Cox and Michael Gove, the environment secretary, in the past two days to try and sell her imperfect deal to Brexiteer MPs.
In a BBC interview on Sunday, Mr Gove with colleagues not to make "the perfect the enemy of the good".
But the problem - seven days out from the vote - hasn't changed: Up to 100 Conservative MPs quite simply think this deal is so bad that they are not prepared to vote for it.
Mrs May's team is hoping that five days of debate in the Commons ahead of the vote next week might - just might - change some minds.
But it felt today that Mr Cox was valiantly defending an unwinnable case.