In the build-up to this incredible rivalry, we bring to you our version of the best combined XI of players from these two teams in the modern day football era since the year 2000.
1. GK - Iker Casillas
Iker Casillas joined Real Madrid at the age of nine and went on to spend 25 years at the club he called home.
Casillas made over 700 appearances for Los Blancos and guided the club to five La Liga titles and three UEFA Champions League titles.
He was instrumental in Real Madrid's most important El Clasico wins in history.
2. RB - Dani Alves
One of the most decorated footballers in history, Dani Alves played at the elite level for the best part of two decades.
The Brazilian full-back has won a whopping 40 trophies in his career, however, it was with Barcelona that he truly made an impact in world football.
Alves revolutionised the right-back role. 23 of his 40 trophies came during his stint with FC Barcelona and that included two trebles.
3. CB - Sergio Ramos
Since making his debut for Real Madrid, Sergio Ramos has come a long way and is widely regarded as the greatest defender of his generation.
The 35-year-old has been widely responsible for El Clasico to become such a major clash in world football.
This list will never ever be complete without Ramos' name in it.
4. CB - Carles Puyol
Puyol made his Barcelona debut back in October 1999 against Real Valladolid.
He quickly rose up the ranks to become the leader of the club and was handed the captain's armband in 2004.
Puyol led Barcelona to many major battles in El Clasico and ensured he returned victorious in most of them.
5. LB - Roberto Carlos
A legend among full-backs, Roberto Carlos represented Real Madrid in many El Clasico clashes.
He made over 500 appearances as a Galactico and won a plethora of silverware, including three UEFA Champions League titles.
Carlos always had a major say in every El Clasico he played.
6. CM - Xavi
Xavi made his Barcelona debut as a teenager back in 1998 and he would eventually grow into the greatest midfielder in Europe a decade later.
Alongside his compatriot, Andres Inesta, Xavi built at glorious dynasty at Barcelona during his time at the club. He won 25 titles with Barcelona, including five La Liga and four Champions League titles.
7. CM - Zinedine Zidane
Arguably one of the greatest midfielders to have ever played the beautiful game, Zinedine Zidane moved to Real Madrid for a world-record €77m from Italian powerhouse Juventus in 2001.
The Frenchman quickly became a fan favourite at the club and over the years in his stint at Santiago Bernabeu, Zidane became one of the biggest legends at Real Madrid.
8. CM - Andres Iniesta
Widely regarded as the best naturally gifted midfielder in football history, Andres Iniesta made his debut for Barcelona in 2002.
His ability to dictate play and dominate the midfield made him the greatest ever to feature for Barca. Iniesta made it a point to come up with some of his best performances in El Clasico.
9. LW - Cristiano Ronaldo
One of the greatest footballers in history, Cristiano Ronaldo brought incredible success to Real Madrid in El Clasico clashes against Barcelona.
Along with his impressive goal-scoring streak in Clasico games, Ronaldo dominated Europe with Real Madrid.
10. RW - Lionel Messi
This list would not be complete it wasn't for Lionel Messi. The Argentine is the greatest footballer in El Clasico history and has led Barcelona to win many battles against their arch rivals.
The six time Ballon d'Or winner will lead his side in El Clasico again on Saturday.
11. ST - Ronaldo Nazario
Regarded as one of the greatest centre-forwards in football history, Ronaldo Nazario boasts the best goalscoring ratio of any Real Madrid player barring Cristiano.
R9 as he was called, ensured he played a starring role for his Real Madrid team in El Clasico clashes whenever he played.