From El Clasico to the Superclasico: What are football's biggest rivalries?
A derby game is always a must-watch for passionate supporters and neutrals alike.
They are the games which mean most, often resulting in heightened tension, drama and excitement — both on and off the field.
Whether it be in South America or across Europe, football seasons are often defined by the outcome of the derby encounters.
Below, we take a look at a selection of some of the biggest and best rivalries in world football.
Barcelona vs Real Madrid
Barcelona and Real Madrid contest one of the fiercest derbies in world football.
Millions across the globe tune in to El Clasico to see who will emerge on top.
This fixture has seen some of the greatest players of all-time announce themselves on the global stage with Lionel Messi, Ronaldinho and Cristiano Ronaldo all scoring crucial goals in recent years.
On-the-field incidents have caused fury and disgust — notably in 2002 when Barca fans threw a pig's head in the direction of Luis Figo — who had left the Camp Nou to join Los Blancos two years earlier.
Tensions also ran high off the pitch in 2011, when Madrid coach Jose Mourinho poked his finger into the eye of Tito Vilanova, Pep Guardiola's assistant in the opposite dugout.
No matter the form of these two Spanish giants, incident and intrigue is guaranteed.
Manchester United vs Liverpool
Manchester United and Liverpool sit 35 miles apart from each other — but not an inch is given when the two sides meet.
With 39 Premier League titles between them, the fight for domestic supremacy has pushed the two clubs to the limit.
Sir Alex Ferguson famously claimed his ambition was to 'knock the Reds off their perch', after decades of success at Anfield.
He successfully did so, though in more recent times Jurgen Klopp has led the Merseysiders back to the summit of English football — but United still offer stern opposition to any title challenge.
AC Milan vs Inter Milan
Italy is renowned for a rich history of club rivalries, but none are bigger than the Derby della Madonnina.
The fixture gets its nickname after the statue of the Virgin Mary on top of the city's iconic cathedral and has become a religious event for the fervent fanbase.
First matching up against each other in 1909, the giants of Serie A have fought for European and domestic dominance for many decades.
While Milan became the first Italian team to win the European Cup in 1963, Inter have enjoyed more recent glory, clinching a historic treble under Mourinho in 2010.
Celtic vs Rangers
The Old Firm is known for its raucous and hostile atmosphere whenever the two Scottish superpowers meet.
With over 100 league titles between them, encounters between the Glasgow rivals often determine the eventual destination of the championship.
Where Rangers were dominant in the 1990s — winning nine consecutive league titles — Celtic have held the upper hand in the 21st century.
The Bhoys won nine league titles in a row to match their neighbour's record of success, but fell short of a famous 10th title this year, with Steven Gerrard guiding the Gers to a first championship since 2011.
River Plate vs Boca Juniors
Football outside of Europe is often neglected by your average fan — but the Superclasico is a fixture that has thrust itself into the spotlight in recent years.
The Buenos Aires derby pits River Plate against city rivals Boca Juniors.
The two sides have a rich history, with Alfredo di Stefano starting his career at River and Diego Maradona famously wearing the blue and gold colours of Boca.
The rivalry drew international attention in 2018 when the second-leg of the Copa Libertadores final between the two sides was moved to Madrid, due to an attack on the Boca team bus prior to the game.
With the first leg having ended 2-2, River went on to clinch an extra-time victory at the Santiago Bernabeu.
Bayern Munich vs Borussia Dortmund
Der Klassiker often serves up a thrilling encounter between Bayern Munich and Borussia Dortmund.
The two rivals have a shorter history than most, meeting only for the first time in 1965.
However, they have both been at the top of the game since then, most notably clashing in a nail-biting Champions League final between back in 2013.
Bayern won the game 2-1 at Wembley, with Arjen Robben's late strike giving Die Roten a memorable victory.
The rivalry is noted for the number of players that have featured for both clubs, with Robert Lewandowski, Mario Gotze and Mats Hummels all having moved from Dortmund to the Allianz Arena in recent times.
Paris Saint-Germain vs Marseille
To round off our list, we must acknowledge Le Classique.
First meeting in 1971, Paris Saint-Germain battled their way towards success in France with Marseille an already established league contender.
Tension has always been present between the two sets of fans but the Parisians have had the upper hand over their arch-rivals since they were bought by their new Qatari owners.
PSG have often emerged as winners since 2010, but that does not take away from the fact that this fixture always brings excitement on a grand scale.