Not only are Novak Djokovic and Rafael Nadal playing for the French Open title on Sunday, they are jostling for position in the race to be crowned the 'GOAT'.

Spanish second seed Nadal, 34, is looking to land a 13th title at Roland Garros, which would move him level with Roger Federer's all-time leading men's tally of 20 Grand Slam singles victories.

Hot on their heels is top seed Djokovic.

The 33-year-old Serb is a year younger than Nadal and seems to have plenty of time on his side over 39-year-old Federer, who did not play in Paris because of a knee injury.

For some, the 'GOAT' discussion is frivolous and does a disservice to the achievements of each player in their own right.

Looking purely at the numbers does not tell the full picture, of course. It is not possible to quantify their different playing styles, how they have adapted their games, their physical and mental strength, nor how they have overcome the tough moments that have peppered all of their careers.

But it does provide the framework for the debate. Here, BBC Sport crunches the statistics for you to consider and then have your say in the comments section at the bottom.

From a clear frontrunner to a three-horse race

The race to be crowned the 'GOAT' - in terms of major titles, at least - is tighter between the top three than it ever has been before.

When Federer overtook Pete Sampras's previous best mark - winning his 15th Grand Slam title, aged 27, at Wimbledon in 2009 - few thought he would ever be caught.

At that stage, 23-year-old Nadal had won six majors and 22-year-old Djokovic had not added to his maiden title at the Australian Open in 2008.

After winning at least one major in every year between 2003 and 2010, Federer's trajectory began to plateau during 2011, the year Djokovic took his game to new heights.

Another Wimbledon title followed in 2012 but then, thanks to a combination of his rivals' brilliance and his injuries, the Swiss did not win another major in the next four years.

Most had written him off as Nadal and Djokovic closed in on his tally, before Federer's renaissance in 2017 - on the back of his rivals stumbling in the race because of injury and loss of form - kept him at least three titles ahead.

That was until last year when Nadal and Djokovic shared the four majors equally between them, leaving the trio closer together than ever.

How do they compare across the different surfaces?

Some argue that Nadal's utter dominance on the Roland Garros clay means he is perhaps not as complete an all-round player as Federer and Djokovic.

The 'King of Clay' has won 12 of his 19 major titles in Paris. Neither Federer nor Djokovic have been as dominant as that at one place, although neither has any other player - male or female - in the history of the sport.

But Federer and Djokovic do each have a Grand Slam they have bossed over the years and at which they hold the record for the number of men's titles won.

Federer has won eight of his 20 majors on the Wimbledon grass, while Djokovic has claimed eight of his 17 victories on the Australian Open hard courts.

One question mark often set against Sampras' record was that he never won a French Open title.

Not succeeding on a particular surface cannot be levelled against these three. Djokovic, however, is aiming to go one step further than his rivals.

With Nadal having won the Australian Open once and Federer doing the same at Roland Garros, Djokovic is aiming to create a piece of history which neither of his peers has managed.

Djokovic, who won the French Open title in 2016, will become the first man in the Open era to win each of the four Grand Slams twice if he wins on Sunday.

Have any of them had 'easier' opposition?

Winning seven best-of-five-set matches in a fortnight is no mean feat.

But, over the course of their combined 56 Grand Slam victories, Djokovic has faced tougher opponents (at least in terms of ranking).

The average ATP ranking of the opponents beaten by Djokovic is 42, against 50 for Federer and 52 for Nadal.

Federer, though, has had to beat more top-10 ranked opponents - 43 of them, compared with 36 for Nadal and 33 for Djokovic.

How have they fared against each other?

This is another area where Djokovic's claims are strengthened.

He has a better head-to-head record against both Federer and Nadal in their total meetings.

In addition, Djokovic has a superior record over Federer in their Grand Slam meetings.

Against Nadal, in Slams only, it is the Spaniard who has the upper hand after winning their first five matches at the majors.

However, Djokovic has won their past three Grand Slam meetings, and Nadal has not beaten him at one since 2014.

But then Nadal has beaten his two biggest rivals the most times on the way to his Grand Slam wins:

How do they compare in terms of longevity?

Aside from Grand Slam titles, the length of time spent as the world number one is another key indicator.

Federer has spent the most weeks in history at the top of the men's rankings. But Djokovic is closing in on him quickly.

After winning the title in Rome last month, Djokovic moved ahead of his idol Sampras.

What about the other big tournaments?

While Grand Slams garner the most attention because of their prestige and unique format, there are plenty of other important tournaments that feed into this conversation.

Of the Big Three, Federer has won the most titles in his career. In fact, only American Jimmy Connors - who won 109 titles - has bettered this tally in the men's game.

Federer also leads the way in terms of winning the end-of-season ATP Tour Finals, considered by most as the fifth Grand Slam.

The Swiss has won six of those events, which see a round-robin group followed by a knockout stage for the world's top eight leading players over the previous season.

Djokovic has won the event five times, while Nadal curiously has never won.

Nadal is a two-time runner-up - losing to Federer in 2010 and Djokovic in 2013 - but has missed four of the past eight tournaments through injury.

Underneath the Grand Slams and the Tour Finals, the next tier of events are the nine Masters tournaments.

Since 2009, these have been held on hard courts in Indian Wells, Miami, Canada (alternating between Montreal and Toronto), Cincinnati and Shanghai, with clay-courts events in Monte Carlo, Madrid and Rome.

This year, only Cincinnati and Rome have been played because of the coronavirus pandemic and were both won by Djokovic.