Whenever you write a world football article about "the greatest ever," you're on a hiding to nothing despite Pele, Maradona and probably Messi and Ronaldo being on everybody's list.
When it comes down to "the greatest No. 10s," there's an even bigger problem. You see, apart from the fact that some No. 10s didn't even wear that number, there is the whole thing about Trequartistas.
Then, if you're not careful, you get sucked into the debate between Trequartistas and Registas. And why is that relevant, you might say?
Well, the thing is that Paul Scholes started his career as a No. 10 and now plays Regista, as does Carrick, Del Piero, even Xabi Alonso and Xavi.
The game has changed. Some of the old Trequartistas have become Registas because that is the way their team plays, and some because they don't have the legs anymore.
Alessandro Del Piero would have made a great No. 10 in the days of Baggio, and he showed that he can have as much effect on the game now in the way he dominated in the Euros from a deeper position.
Similarly, the Manchester United fans who constantly carp at Michael Carrick simply don't understand that he is under instructions from Sir Alex Ferguson to play as a Regista. As Ray Wilkins said in summarising his performance against Newcastle, "he was absolutely outstanding."
But he won't be on our list.
And we're not talking about Trequartistas here, even though some of the names here have played that way and one of them invented it.
And no, the chosen few didn't necessarily even wear the number. But if you've been around football long enough, you'll recognise this chosen 10 as what they are or were.
Denis Law was a No. 10 and started his football in the times of 2-3-5, so he would originally have been called an "inside forward," as was Johnny Haynes, who also wore the shirt. But Jimmy Greaves was a No.10, as we would understand it, playing off Alan Gilzean wearing nine.
Now we're going to create a little twist here, because you've probably read articles like this before or had a heated discussion in a bar.
So, we shall only choose one from each country while mentioning some of the other greats in passing.
Before we start, who would be your 10 greatest on that basis?
Wayne Rooney could be entering the best phase of his career, one in which he could irrevocably become regarded as a world footballing great.
His partnership with Robin Van Persie
RVP in his earlier career would have been regarded as a No.10. There is no doubt that one of the factors which can make this partnership special is the ability for either to play "in the hole" behind the main striker. You can comfortably expect over 40 goals from this pairing this season.
His ability to play a number of roles as needed
Now that Sir Alex has seen the light, you can expect to see Wayne play a number of roles as needed for United.
He can play the traditional No. 10 in his sleep, whether it is behind a lone striker or a pair, as he did on Sunday.
He brings great versatility to the role, however. Despite his nominal position, he could be found all over the park. At least twice, he was the last man clearing a Newcastle attack. He broke up play in midfield. And he gave two assists.
He has previously stated that he would be happy to end his career in midfield, and in recent matches, he has been spraying more and more Scholes-like passes.
Paul Scholes was one of the other two England No. 10s to be considered. In his earlier career, that is the role he so often played. Making the last pass or popping up in the box to volley or head a goal.
He has not played that role for several years now, however, which is a pity. If he had strong enough players around him to do the running, he could sit on top of Carrick and orchestrate the top of the game. The trouble is that everyone has to defend now, so Scholesy is usually closer to the back.
Steven Gerrard should also have been a classic No. 10 for his entire career. With his tackling ability as a bonus, he was made for the role. He was Ian Callaghan to Fernando Torres. The trouble is, Liverpool don't have enough world class players, so Steven plays deeper, as indeed he does for England.
Georghe Hagi was a true "Galactico" at Real Madrid. But how great could he have been if he had played for Argentina, Italy or Brazil?
He suffered a similar misfortune to George Best, another genius. If either had played for a top nation, they would have been even better and better remembered.
Hagi was idolised in Roumania and almost single-handedly made them into contenders. He is one of the few players to play for both Real Madrid and Barcelona.
He deservedly makes this list.
Brian and Michael Laudrup and Peter Schmeichel were the greatest things to happen to Danish football.
Ironically, having fallen out with the coach, Michael quit the Danish national team in 1990 during the Euro 1992 qualifiers. Denmark "came off the beach" at the last minute to win the tournament.
Michael also played for both the "El Clasico" teams. He is regarded as one of the most technically accomplished players ever and one of the best passers of a ball.
In many ways, he was similar to Paul Scholes at his best. He had the all-round vision to see an opening and thread a pass, shearing defences like the Red Sea.
Now 48, he is regarded by the Swansea players that he manages as the best footballer in the club.
"The Black Panther" for much of the last 50 years would have featured on most people's lists as one of the greatest footballers ever. Forty years ago, he would have been second to Pele. And yet he hardly ever features in lists of the great No. 10s.
Maybe its because Portugal have never been a fashionable side, like Roumania. Even Ronaldo hasn't managed to make them great.
The video gives an insight into how great he was. Playing for Benfica, they were one of the best teams in the world.
You had to see Baggio to realise how good he was. Notice the behind heel pass early in the video. Some people think Cristiano Ronaldo invented that.
He is in good company. Arguably the best No. 10 currently playing in Italy is Francesco Totti, now 36. But he's not in Baggio's class.
Roberto was voted fourth-best player of all-time in the FIFA Internet poll and a member of the all-time FIFA World Cup Dream Team. He also won the Ballon D'Or and FIFA World Player of the Year in 1993.
He is also one of the greatest Italian goalscorers of all time on many different counts, scoring 218 in 488 matches at club level and 27 in 56 for his country.
In some ways he was more than a great No.10 and probably the first true Trequartista in Italian football.
Johann Cruyff was the father of Barcelona's modern style of football. Its roots were in the "Total Football" played by the great Dutch side of the 1970s.
Rinus Michels is credited with the creation of Total Football at the great Ajax side, and it was carried into the Dutch national team. In some senses, the concept was built round Cruyff.
Michels later went to Barcelona, and Cruyff followed, modifying the ideas into what is now known as Tiki Taka football.
Cruyff was also a footballing genius. He was neither a No.9 nor a true No.10 because of his freedom to play wherever he wanted. As the video shows, he could create or execute goals from almost anywhere.
Cruyff and the Dutch side inspired generations of expressive, talented and intelligent footballers. Ajax is still a production line for such players.
The other Dutch candidate for No. 10 was Denis Bergkamp, who was, in many ways, the creative genius for Arsenal during his stay. But Cruyff was in a different league.
Diego Maradona might have made second place in this review had it not been for his blatant cheating in the World Cup match against England and his history of drugs.
It is beyond belief that a footballer with such a history, let alone alcoholics like George Best, can be regarded as idols in a sport that so many young people aspire to achieve at.
Lance Armstrong and others have become pariahs in their sports for drug abuse. Chelsea cancelled Adrian Mutu's contract because of recreational drugs.
But Maradona became Argentine national coach.
There is no doubt he was one of the most gifted footballers in the history of the game. For that reason, he edges Lionel Messi as the greatest Argentinian No.10 of all-time.
There is some debate about whether Messi, Xavi or Iniesta is the true No.10 in a Barcelona team with up to six midfield players and no striker. But one day, Messi may well be regarded as the best player of all-time anyhow.
Each will have their devotees, but the choice here is Michel Platini.
Zinedine Zidane was also a Real Madrid Galactico, arguably one of the best ever. He joined them for a world record 75 million Euros in 2001. In 2003, he was voted FIFA World Player of the Year, and in 2004, the best European footballer of the previous 50 years in the "Golden Jubilee Poll."
He was arguably the star of the greatest French team ever assembled that won the World Cup in 1998 and the European Championships in 2000.
Michel Platini is one of the best passers, free-kick specialists and finishers in footballing history. He is currently UEFA president.
Notwithstanding his role at the top of midfield, he had a goal-scoring record that any striker would die for. He scored 224 goals in 432 club matches and 41 in 72 for his country.
Unfortunately, the French national team he played in wasn't as successful as Zidane's, but Platini was in the 1984 European Championship-winning side.
He won World Soccer Player of the Year twice, European Player of the Year and three Ballons D'Or.
Maybe the reason that he is not regularly voted the best player that ever lived is because Ferenc Puskas lived at a time when there was far less recording of top football.
It was also a time when footballers used a heavy lace-up leather ball that could be like a cannonball when wet. Despite that, he was arguably the greatest footballing genius of all-time.
When you watch the video, Puskas is the No. 10 and Di Stefano the No. 9 in the Real Madrid strip. Both players were prodigious in possibly the greatest Real Madrid side ever. Puskas is the guy doing the "lollipops, step-overs and back-heels."
There can be few strikers who have scored at a better rate than Di Stefano, with 216 in 282 matches for Real Madrid and 400 in 522 in all top-class football. He was the striker.
Ferenc Puskas is regarded by some as the first true Trequartista, but for now, we'll keep him as a No.10. Like Cruyff, Baggio, Platini and Maradona, he could skip through defences, beating one man after another before either slipping an assist or curling the ball into the net.
His own goal-scoring record is simply astonishing, consistently scoring at a goal a match. His club record was 616 in 620 matches, and for Hungary, he had 84 in 85.
He played at the highest level of football for 23 years, finishing his career at 39. Hungary was the great national side that humiliated England in 1953 and probably changed football forever. They undoubtedly had an influence on Rinus Michels, and the Dutch school that became Total Football.
How great could Pele have been if the opposition hadn't set out to kick him off the park?
Edison Arantes do Nascimento is routinely voted the greatest player that ever lived. He just happens also to be the greatest No. 10, of course.
To put him in a Brazilian perspective, we could have picked Zico or Ronaldinho instead, but frankly, it was no contest. Watching the video, you can see where Ronaldinho got some of his tricks.
When I was young, Real Madrid was the club side I delighted in watching, and Brazil's national team. Sir Matt Busby and Sir Alex Ferguson probably had similar influences, but they were also old enough to remember the Hungarian side.
We all retained a passion for great individual footballers that defined the "beautiful game." Manchester United might well have signed Puskas after the Munich Disaster if not for FA rules on overseas players.
Pele, however, never left Santos and Brazil until his twilight years when he went to New York Cosmos, playing into his 40s.
His scoring record was almost as impressive as Puskas' with 589 in 605 for Santos, and 77 in 92 for Brazil.
He did not have the bodily strength and solidity of Puskas, and sadly, the 1966 World Cup was marred by him being kicked systematically by Bulgarian and Portuguese players until his body failed. This was the second successive World Cup where he missed matches through injury.
He first played in the World Cup in 1958 at the age of 17, and in all, won three titles. Who knows whether Brazil rather than England wouldn't have won in 1966 if he had played throughout.
He gained the No.10 shirt by accident. Brazil had forgotten to allocate numbers, so FIFA did it instead, and Pele was nominated as No. 10, still the greatest and the best footballer of all-time.
For the young and those with short memories, Lionel Messi has widely been suggested as the greatest footballer of all time. This seems premature, considering some of the facts given previously.
Furthermore, how do you decide whether he is a No. 10 in the classic sense when Barcelona typically play six midfielders and no striker?
He does at least wear the No. 10 on his back.
So let's for the time being nominate him as the best contemporary bearer of the shirt.
Not in any particular order, here are another nine who are still playing:
Scholes and of course
So who do you think is the best No.10 ever; and who the best of the contemporaries?