Iker Casillas is widely regarded as one of the greatest goalkeepers in history.

At Real Madrid, 'The Saint' was a world-class performer for well over a decade and he won a plethora of trophies as a result, including five La Liga titles and three Champions Leagues.

But while Casillas was incredible for his boyhood club, there's an argument to be made that he was even better on international duty with Spain.

The 40-year-old was La Roja's main man between the sticks when they won two European Championships and a World Cup in the space of four years.

Casillas was sensational throughout that memorable run and rarely ever put a foot wrong during the entirety of his 16-year international career.

That's proven by the great man's superhuman-like numbers.

JOHANNESBURG, SOUTH AFRICA - JULY 11: Iker Casillas, captain of Spain, celebrates the late goal by Andres Iniesta during the 2010 FIFA World Cup South Africa Final match between Netherlands and Spain at Soccer City Stadium on July 11, 2010 in Johannesburg, South Africa. (Photo by Clive Mason/Getty Images)

No goalkeeper in the 21st century has kept more clean sheets on the international stage than Casillas and it's not even close.

Check out just how far he is ahead of the rest by looking over the data below collected by PopFoot...

20. Andriy Pyatov (Ukraine)

Games: 101 | Clean sheets: 46 | Clean sheet percentage: 46%

19. Wayne Hennessey (Wales)

Games: 100 | Clean sheets: 46 | Clean sheet percentage: 46%

18. Vincent Enyeama (Nigeria)

Games: 91 | Clean sheets: 46 | Clean sheet percentage: 51%

17. Manuel Neuer (Germany)

Games: 109 | Clean sheets: 47 | Clean sheet percentage: 43%

16. Sergio Romero (Argentina)

Games: 96 | Clean sheets: 47 | Clean sheet percentage: 49%

SAO PAULO, BRAZIL - JULY 09: Sergio Romero of Argentina celebrates saving the penalty kick of Wesley Sneijder of the Netherlands (not pictured) in a shootout during the 2014 FIFA World Cup Brazil Semi Final match between the Netherlands and Argentina at Arena de Sao Paulo on July 9, 2014 in Sao Paulo, Brazil. (Photo by Matthias Hangst/Getty Images)

15. Igor Akinfeev (Russia)

Games: 111 | Clean sheets: 48 | Clean sheet percentage: 43%

14. Thibaut Courtois (Belgium)

Games: 94 | Clean sheets: 48 | Clean sheet percentage: 51%

13. Tim Howard (USA)

Games: 121 | Clean sheets: 49 | Clean sheet percentage: 40%

12. Rui Patricio (Portugal)

Games: 102 | Clean sheets: 49 | Clean sheet percentage: 48%

11. Andreas Isaksson (Sweden)

Games: 133 | Clean sheets: 52 | Clean sheet percentage: 39%

STOCKHOLM - APRIL 30: Andreas Isaksson of Sweden in action during the International Friendly match between Sweden and Croatia held on April 30, 2003 at the Rasunda Stadion, in Stockholm, Sweden. Croatia won the match 2-1. (Photo by Ben Radford/Getty Images)

10. Fernando Muslera (Uruguay)

Games: 130 | Clean sheets: 52 | Clean sheet percentage: 40%

9. Guillermo Ochoa (Mexico)

Games: 126 | Clean sheets: 52 | Clean sheet percentage: 41%

8. Shay Given (Republic of Ireland)

Games: 107 | Clean sheets: 52 | Clean sheet percentage: 49%

7. Edwin van der Sar (Netherlands)

Games: 87 | Clean sheets: 54 | Clean sheet percentage: 62%

6. Claudio Bravo (Chile)

Games: 143 | Clean sheets: 55 | Clean sheet percentage: 38%

KAZAN, RUSSIA - JUNE 28: Claudio Bravo of Chile celebrates winning the penalty shoot out after the FIFA Confederations Cup Russia 2017 Semi-Final between Portugal and Chile at Kazan Arena on June 28, 2017 in Kazan, Russia. (Photo by Laurence Griffiths/Getty Images)

5. Petr Cech (Czech Republic)

Games: 125 | Clean sheets: 56 | Clean sheet percentage: 45%

4. David Ospina (Colombia)

Games: 123 | Clean sheets: 61 | Clean sheet percentage: 50%

3. Hugo Lloris (France)

Games: 137 | Clean sheets: 62 | Clean sheet percentage: 45%

2. Gianluigi Buffon (Italy)

Games: 164 | Clean sheets: 72 | Clean sheet percentage: 44%

1. Iker Casillas (Spain)

Games: 168 | Clean sheets: 102 | Clean sheet percentage: 61%

Iker Casillas World Cup
JOHANNESBURG, SOUTH AFRICA - JULY 11: Iker Casillas, captain of Spain, celebrates victory with the World Cup trophy during the 2010 FIFA World Cup South Africa Final match between Netherlands and Spain at Soccer City Stadium on July 11, 2010 in Johannesburg, South Africa. (Photo by Laurence Griffiths/Getty Images)

Casillas is the only man to surpass the 100 mark and sits a cool 30 clean sheets ahead of Buffon in second place having played only four games more - outrageous stuff really.

The Spaniard also possesses the second-best clean sheet percentage on the 20-man list, with Van der Sar the only man possessing a better record in that regard.

Yeah, Casillas was pretty darn good and if anything, his career is slightly underrated by the masses in the present day...