She was rushed to nearby St Mary's Hospital in Paddington, where X-rays confirmed she had fractured her left wrist. An undoubtedly sorry end to the evening for Ms Mazo, but given the extraordinary turn of events that have followed, sympathy for the self-employed Spanish human resources consultant is likely to be in short supply.
For having successfully sued the pub for compensation - and been offered a generous £150,000 or so for her injury in 2014 - Ms Mazo (who, by the way, is right-handed) has declined the sum and is returning to court to demand a mind-bogglingly precise £4,235,004.77.
Even among the 'slippers and trippers' who have become the bane of Britain's burgeoning compensation culture, Ms Mazo's claim is outlandish to say the least.
More in a moment about the mathematical gymnastics that have led her lawyers to claim that extraordinary sum on her behalf. But it vastly dwarfs the highest amount that can be paid out to injured British Armed Forces personnel suffering loss of limbs or paralysis while serving, a figure capped by the Government at £570,000.
Ms Mazo, who is now 41, claims she deserves those millions because her life has been destroyed by her one false step on the paved terrace of The Westbourne.
Thanks to 'a bartender's irresponsibility', she opined, her career has been destroyed, her mental health and social life ruined and she has been left with scars on her wrist that make it look as if she's been self-harming.
"I have been left with what I consider to be horrendous scars on my wrist from the surgery,' she said in court. 'I could end up with no career or purpose in life."
Documents seen by the Mail this week also reveal that Ms Mazo expects to be compensated for the future cost of regular leg waxings, manicures, pedicures and blow dries; activities she is apparently no longer able to carry out herself.
She also wants money towards taxis and acupuncture.
But the bulk of the millions she wants are to compensate her for future loss of earnings - an amount far in excess of anything she had earned in the past.
"I'm surprised she's been given leave to appeal,' says Anthony Baker, a partner at Plexus Law, who specialises in defending insurance companies from personal injury claims.
"It seems preposterous to me that a human resources consultant, which is essentially a sedentary role, should in any way have significant compensation for loss of future earnings, because a broken wrist won't prevent her being an HR consultant.
"I struggle to see how a claim like this could be worth those sums or how the courts could increase what is already a significant compensatory award."
Indeed, closer analysis of the facts at the heart of this troubling case raises serious questions about how on earth Ms Mazo has been allowed to appeal an already generous settlement and pursue a sum that would make her a multi-millionaire.
Little is known about her personal circumstances aside from the fact that she attended university in Spain and moved to the UK about 16 years ago. She is single and does not have any children.
One of her first homes in Britain was at the Christian Alliance Centre near Waterloo Station, a low-cost, long-stay hostel popular with European students and young professionals embarking on a career in London. More recently she has been sharing a rented flat in the same area of South London.
The fracture she suffered in August 2009 was a complex one. Her wrist was initially placed in plaster at St Mary's Hospital and she was then referred to Chelsea and Westminster Hospital. There, she underwent surgery to insert a metal plate and screws on September 3, and afterwards had physiotherapy.
According to medical testimony, her recovery was "excellent".
Notes made following an outpatient's appointment in January 2010 read: "Completed hand therapy. Outcome excellent ... Miss Mazo is delighted with the outcome of her treatment ... Now using and moving the left wrist and hand and planning to restart flamenco dancing."
Ms Mazo, who set up her own limited company in May 2008, through which she paid herself, returned to work in April 2010, having taken seven months on sick leave.
Her career in human resources appears to have revolved around short-term contracts for London borough councils, including Islington, Brent, Barking and Bexley.
For three years, between April 2010 and May 2013, she continued to work, and while she later claimed typing made her wrist hurt and she was suffering post-traumatic stress disorder, depression and constant pain, legal documents reveal that none of her colleagues appear to have noticed that anything was wrong with her.
According to one member of staff who worked with her during her last contract, before she stopped working in May 2013: 'Carmen made no reference to any difficulty she had working. She used a standard keyboard without complaint for the entirety of her contract.
"I can say quite categorically that any accident that took place in no way hampered her ability to complete her contract for the council."
During that last brief contract, Ms Mazo was earning £500 a day, but insists that because her career was on an 'upwards trajectory', she could have looked forward to upwards of £700 a day if she had been able to continue working.
In fact, employment records and emails clearly show that the rate she could demand varied vastly from £200 to £500, depending on how quiet the job market was.
Furthermore, public records seen by the Mail suggest that Ms Mazo's company, Move On Consulting Ltd, wasn't exactly raking it in. In May 2009 - three months before her accident - the year-end total of cash in the company's bank account was just £14,000.
The legal waters surrounding this case have been further muddied by the fact that in April 2010, just weeks before she returned to work, Ms Mazo was diagnosed with endocarditis, a heart infection that had absolutely nothing to do with her wrist injury, and was admitted to hospital for a fortnight.
A year-and-a-half later, she returned to Madrid for surgery on her aortic valve and underwent two further "operations to minimise the scars left behind on her chest".
Ms Mazo claimed in court that the 'horrendous' scars on her wrist were 'a constant reminder of the chest scarring'.
According to Professor Thomas Fahy, an NHS consultant psychiatrist, it was the heart surgery, not the wrist accident, which had sent Ms Mazo into a decline.
In her original judgment on the case, Judge Heather Baucher summed up Professor Fahy's view that "if the accident had not occurred, the claimant would probably have been the same. He thought the claimant had gone into decline, probably post-heart surgery and that was a watershed".
Both he and another psychiatrist hired by Ms Mazo's team were in agreement that 'Miss Mazo's cardiac problems and the litigation have had a detrimental affect on her mental health'. Both agreed that she needed further therapy.
There were clear references, too, to the fact that Ms Mazo was already prone to some kind of depression before the accident.
"My career has always been my refuge to block away unpleasant circumstances in my personal life,' she told the original hearing.
"Now I am finding that because of a bartender's irresponsibility, I could end up with no career or purpose in life. I cannot stop worrying about my scars, my future, and I am in constant pain."
Another expert witness who gave evidence at the 2014 hearing, Rupert Eckersley, an orthopaedic hand and wrist surgeon who examined Ms Mazo, said that there was 'significant psychological vulnerability prior to the accident, which had affected her confidence levels and self-esteem rendering her vulnerable to preoccupation with health-related issues'.
Judge Baucher examined the wrist scar in December 2014. "It was so faint it was not visible at a short distance," she said.
"I had to look at it at close examination to see it.
"The fact the claimant ordinarily wears a bracelet to hide it is entirely a matter for her, but for anyone to believe it was suggestive of self-harming, as she contended, would require them to be very close and personal with her."
Most damning of all, however, was Judge Baucher's comment that Ms Mazo was "extremely volatile and aggressive when cross-examined".
She added: "I did not find the claimant to be a credible witness."
Why on earth, then, has Ms Mazo been given leave to appeal the original judgment, which granted her a more than generous sum of £156,871.82, given that so many doubts were raised about her credibility and the scope of her claim?
One legal expert told the Mail last night that it was simply a matter of procedure; that while Ms Mazo had been given permission to appeal, it was highly unlikely that the original judgment would be overturned unless the original judge was seen to have erred legally by the three senior judges who will review the case.
Andrew Parker, a personal injury expert at DAC Beachcroft, who has advised the Government and insurance companies on civil litigation, adds: 'She has already got a substantial reward by any view.
"Though each case must be judged on its facts, what I sense here is that she clearly blames everything that has happened to her on this accident and I do think we have a cultural problem around that. People are always looking for someone or something to blame and that's a bit of the feel of this.
"Wherever you see someone who wants a lot more than a court has been prepared to give them, I've seen those cases time and time again and the reality is usually something different."
Indeed, much reference was made at the original hearing to Ms Mazo's obsession with her legal complaint and the belief the litigation was, in fact, perpetuating her illness.
As Judge Baucher put it: 'In short, these proceedings became her focus. She now lays everything at the door of a 'bartender's irresponsibility'."
For the time being, then, there is still no resolution to this troubling case. No date has yet been set for any future hearing, though, given the current backlog of cases going through the High Court, it could take up to 18 months.
In the meantime, it is impossible to know for sure exactly how Ms Mazo's life has been affected by that split-second fall in 2009.
She claims to have three disabilities: arthritis, scarring and depression, "all caused by the accident". But she looked cheery enough when she flicked a Churchillian 'V' sign with her right hand from the steps of the Royal Courts of Justice earlier this week.
Having been given leave to appeal, if she ultimately wins her court case, then she will certainly have further cause to celebrate.
So, too, will the ambulance- chasing "no win, no fee" law firms who make millions when claims like these are settled or won.
For now, however, this sorry legal drama drags on.
It's business as usual at The Westbourne pub, though owner Sebastian Boyle, a former boyfriend of Jade Jagger, was not available for comment. Any future payout will be made by his public liability insurers rather than coming out of his own pocket.
But while he gets on with his life, Ms Mazo's appears to be suffering under the weight of her legal action.
For surely the scars on her wrist will be as nothing when compared to those left behind by a costly and bitter court case which, six years after she fell, as yet shows no sign of concluding.
- Daily Mail
