Before we get into this impossible debate, I am setting up some parameters. We are not debating off-court achievements, nor crowd favouritism, nor how gracefully our players, who are only drawn from the Open era, might have conducted themselves.

Instead, I am imagining a Marvel-style battle for the existence of our planet, based on a single tennis match against an unknown challenger from a parallel universe. And the choice of surface will be determined by the roll of a dice. Deep breath, here goes.

10. Monica Seles

Might arguably stand at No 1 but for the tragedy which unfolded in Hamburg in 1993, when her career was derailed by a knife-wielding Steffi Graf obsessive. At that point, Seles’s relentless double-handed pounding off both wings had won her 55 out of her last 56 matches at the majors – an astonishing statistic – with the only defeat being a heavy loss to Graf in the 1992 Wimbledon final.

One of Seles’s great assets was her see-ball, hit-ball simplicity: there simply was not a lot to go wrong, and she never over-complicated what is essentially a straightforward game in her own mind. But she never did win Wimbledon, which is one reason why she comes in relatively low on this list.

9. Bjorn Borg

Tricky one, this. Borg had a relatively short career but his record is so good that I’m giving him a chance in my squad. Never won the US Open, which was played on grass in his era, and only made the trip to Australia once, but still maintains a 90 per cent win rate at the majors, which only Graf can match on our list.

In her case, that is boosted by a lack of great rivals; in his, the decision to walk away from the sport at his physical peak, aged 26. Despite the glamour of Borg-mania, he played a very conservative style, based on the elimination of error and superhuman stamina. Famously had a resting heart rate of just 35 beats per minute.

8. Rafael Nadal

I am sure I will get slaughtered for this but the fact is that we are rolling a dice for choice of surface, and there is only a one-in-three chance of the match being played on clay. Clearly, Nadal’s clay-court record is in a different universe to anything else we have seen in the history of tennis.

At Wimbledon, though, his win percentage of 83 is good but not great, exposing the relative vulnerability of his serve. At the two hard-court slams, that figure ticks up to 84, but at Roland Garros it reached a mind-boggling 97.

7. Rod Laver

‘The Rocket’ only comes into our calculations briefly, as he played most of his career before the advent of the Open era, but to win the calendar grand slam in 1969 (as he had in 1962 before turning pro) was a rare and historic feat which has yet to be repeated in the men’s game.

Tough as crocodile skin, this Queensland boy stood just 5ft 8in tall but was renowned for the size of his Popeye-ish left forearm and the quality of his volleys. The only serious contender who prefigures the Borg revolution of the 1970s.

6. Chris Evert

The ice maiden of tennis, Evert’s astonishing 80-match rivalry with Martina Navratilova puts even the ‘big three’ men in the shade. Even more remarkably, 60 of those meetings came in finals, with Navratilova shading the results by 43 to 37. As with the Roger Federer-Nadal rivalry, this was a brilliant contrast of styles and personalities, in which Evert’s remorseless baseline accuracy offered a sort of Sicilian Defence against her opponent’s net-rushing aggression.

Also, has anyone ever kept a cooler head on the court? Evert joins Nadal in that rare category of players who never threw a wobbly.

5. Roger Federer

Federer’s all-court mastery is obscured by the fact that he was trying to win the French Open at the same time as Rafael Nadal. In fact, he is the only man to win 10 titles on each of the three surfaces – even if this statistic also reflects Djokovic’s disinclination to play grass-court warm-up events before Wimbledon.

An incredible frontrunner whose win percentage from the moment he landed his first grand-slam title (Wimbledon 2003) until the end of 2007 touched 92 per cent, with 12 majors banked from a possible 20. After that, Nadal and Djokovic limited Federer to a mere eight more major titles, but his re-emergence in 2017, with a turbo-charged backhand that upstaged his old rivals, must go down as one of the most romantic sporting comebacks.

4. Martina Navratilova

Navratilova’s career took a while – and a defection from Czechoslovakia to the USA – to flower. But she truly blossomed in her late 20s, after switching to a graphite racket and taking fitness seriously. An explosive athlete whose pace and power combined with perfect volleying technique to make her almost unbeatable at Wimbledon, where she won six straight singles titles from 1982 to 1987.

During that purple patch, Navratilova lifted 14 out of 21 majors and was runner-up four times as well, while registering a mind–boggling tour win percentage of 95.

3. Steffi Graf

Another bulletproof mental monster, ‘Fraulein Forehand’ won the golden slam (all four majors plus the Olympic gold medal in singles) and at least four titles at each of those slams, despite slicing the vast majority of her backhands. Her win percentages are extraordinarily high – a massive 89.75 at the majors, for example – and she handed out some frightening beatdowns in major finals, including the notorious double bagel over Natalia Zvereva at the 1988 French Open. On the downside, Graf rarely had to deal with a really strong rival, with Arantxa Sánchez Vicario being her nearest challenger for a lot of her career.

2. Novak Djokovic

Has proved beyond doubt that he is the greatest male in tennis history, with an unparalleled level of balance between the three different surfaces. Indeed, balance is the key to Djokovic’s game. His ability to slide on any surface probably derived from a childhood spent on the ski slopes of Kapaonik, a Serbian mountain retreat, and his uncanny flexibility has allowed him to retrieve apparently impossible situations on countless occasions during his career.

Not the most elegant or charming player to watch but a perfectly calibrated winning machine and, mentally, the toughest nut out there.

1. Serena Williams

Simply the most irresistible force I have seen on a tennis court, with the greatest locker-room power of all time. Won 23 majors despite losing interest for a significant period in the mid-Noughties, and then becoming a mother when she was still a dominant force at 36. There is a strong case that 23 majors represents an underperformance for a woman whose whole package – technique, physicality and mentality – was as superior to the field as Simone Biles is to other gymnasts.

And look at what Serena was like when she really wanted to win – or, in other words, when she played Maria Sharapova. She won 19 straight matches, from 2005 to 2019, dropping a measly three sets in the process. I want that Serena to play for Earth’s future.

Now, have your say: