It's far from easy to quantify the accomplishments of great players in any given sport. Who are the top 4 hockey players of all time: Wayne Gretzky, Bobby Orr, Mario Lemieux, Maurice Richard? How about gridiron football? Or baseball, which has so many greats.

As a sport, soccer is more widespread than any game on the planet. There are so many national teams, and along with these teams come world-class players. These national sides participate in a variety of competitions such as the European Championship (Euro Cup), the Copa Sudamerica (South American Championship), and of course, the World Cup, which spans the entire globe.

How does one compare a player's contribution to a given competition? And then face the difficult task of judging a player's impact in terms of club play; is a top-scoring title in one league worth more than another?

With all of these different aspects to consider, selecting the 20 greatest soccer players of all time is a daunting task. English fans will be partial to players such as Bobby Charlton, Stanley Matthews, George Best, or even David Beckham. An Italian fan might include Giacinto Facchetti, Dino Zoff, and Paolo Rossi. Turn to South America and you would see names like Garrincha, Vava, and of course Pele and Maradona.

There's no doubt that all of the players mentioned are great in their own respect, but to be one of the greatest of all time, a player must have added something more to the game itself. It is not simply a matter of goals and saves.

Based on the following criteria, here are the top 20 greatest soccer players of all time:

• Contribution to the success of their nation;
• Contribution to the success of their clubs;
• If a forward player, the quantity and quality of their goal tallies for club and country;
• If a midfield player, the command with which they controlled matches, along with their goal tallies;
• If a defender, the ability to foil high-quality attacks and take charge of their half of the field;
• If a goaltender, the impact of keeping their team in contention during big matches;
• He might be currently playing or retired;
• He might have gone on to successfully coach a club or a country;
• And most importantly, the type of legacy the player left in the wake of his career.

  Basically, a footballer who is a national hero or a club legend must obviously be considered one of the greatest. Read these players' biographies and decide for yourself whether they would be included in your top 20.

Why he's one of the greatest: Chose to stay with Italian club Fiorentina despite relegation to the Serie B in the 1992/1993 season, to lead them back to the Serie A the following season.

Gabriel Batistuta made his name with Argentine club Boca Juniors after a short stint at rivals River Plate. He gained prominence on the world stage in 1991, scoring six goals as Argentina took the South American Championship. His performance prompted a move to Italian side Fiorentina, where fans affectionately nicknamed him "Batigol" for his predator's touch. Choosing to remain with Fiorentina following relegation, Batistuta earned the Serie A scoring title the following season with 26 goals. After nine seasons with Fiorentina, he was sold to AS Roma, where his 20 goals would inspire the side to their third ever Italian league title.

Batistuta remained a faithful member of Argentina's national side throughout the 1990s. His two goals against Mexico in the 1993 South American Championship final saw Argentina hoist their second consecutive trophy. Always the marksman, he led the team in goals at both the 1994 and 1998 World Cups. Unfortunately for the world-class striker, the imminent transfer to the "big club" never came.