Derbies are usually the highlight of every team's season.
These aren't your average, run-of-the-mill fixtures. They're brimming with intensity, passion and in some cases, deep-seated hatred.
Try saying 'it's only a game' to any supporter on Derby Day and you'll be greeted with a list of reasons why for each club, there's one game that matters more than any other.
That said, some rivalries are so heated and can draw on so much history that they aren't just important to their own fans.
Around the world, occasions like the Superclásico and the Old Firm attract millions of viewers who can't wait to see what fireworks are sparked.
In 2019, FourFourTwo decided to list 50 of the very best derbies from around the world and we feel they're got their list pretty spot on, with a few minor dubious points along the way.
50. Sheffield United vs Sheffield Wednesday
It's a pity the divisions have often kept these two bastions of Yorkshire steel apart in recent years as the passion in the stands is unrivalled.
49. Blooming vs Oriente Petrolero
You might not be familiar with the goings-on in Bolivia's Santa Cruz but the fixture did attract headlines farther afield when in 2008, an Oriente Petrolero player celebrated scoring by dancing like a chicken - it led to a mass brawl and three players were sent off.
48. Portland Timbers vs Seattle Sounders
MLS fans are often mocked for not being as - shall we say - raucous as their counterparts in Europe and south America. However, one possible exception is when the Timbers and Sounders get together for the States' biggest derby.
47. Lyon vs Saint-Etienne
Le Derby was firmly in Lyon's hands for years during their most dominant spell in Ligue 1.
46. Newell’s Old Boys vs Rosario Central
Newell’s Old Boys is about far more than its most famous supporter, Lionel Messi, and it's always a spectacular affair when they meet Rosario Central in Argentina's third-biggest city.
45. Athletic Bilbao vs Real Sociedad
They have their differences, but Bilbao and Sociedad are often united during the Basque derby in shows of strength against the central government in Madrid.
44. Everton vs Santiago Wanderers
Everton de Vina del Mar in Chile once won this fixture 17-0 many, many years ago, but have since fallen on tougher times after relegation in 2014.
43. FC Seoul vs Suwon Bluewings
LG Cheetahs, now FC Seoul, moved cities twice in the last two decades but the animosity hasn't gone away, wherever they've played.
42. Bahia vs Vitoria
In the Brazilian city of Salvador, early players from the two teams were so desperate to secure victory they used to make offerings to different gods.
41. Dynamo Moscow vs Spartak Moscow
The oldest derby in Moscow. Spartak's origins lay in the trade unionist movements of 1922 and Dynamo were formed a year later.
40. America vs Deportivo Cali
The two clubs have more than their fair share of heartache between them but they're more than happy to inflict it on one another when they get the opportunity.
39. Hamburg vs St. Pauli
Whatever you make of the action itself, the German police rated it as the country's most violent derby. It's been marred by hooliganism over the years, though it's hardly alone in that.
38. Alianza Lima vs Universitario
The greatest football clubs Peru has to offer. In the very first game between the pair, Alianza had five players sent off after falling behind. The kind of sore losing we can all get behind.
37. CSKA Sofia vs Levski Sofia
Another fixture that has seen its fair share of flare-ups over the years, Levski did not welcome CSKA Sofia encroaching on their territory - after all, they only formed in 1948.
36. Cerro Porteno vs Olimpia
Paraguay quite literally comes to a standstill when these two sides play as 90% of the entire population support one of them. The game's got a bit more sophisticated over the years; Olimpia forgot to turn up to their first ever derby.
35. Glentoran vs Linfield
Northern Ireland's biggest two sides are miles clear of any other side in the region. Linfield have won the league 53 titles and Glentoran 23.
34. Barcelona vs Emelec
Not *that* Barcelona, obviously. This is the side who have been the biggest force in Ecuador's Serie A, beating all before them including their local rivals from Guayaquil, the country's biggest port town.
33. Esteghlal vs Persepolis
At least there are no arguments over who has the better stadium in Tehran. Conveniently, they both share the Azadi Stadium, which is always packed with 95,000 when its two teams play one another.
32. Dinamo Bucharest vs FCSB
FCSB are the club formally known as Steaua Bucharest (that changed after a dispute with the army). In the Communist era, they were helped to strengthen their playing sides with funds from the Romanian state. They also banned players under 28 from moving abroad.
31. Kaizer Chiefs vs Orlando Pirates
A combined 30 million people support the two South African giants. Kaizer Chiefs were actually born out of the in-fighting at Orlando Pirates, which convinced their former player Kaizer Motuang to start up his own club.
30. Genoa vs Sampdoria
Now this is what you call history. Their hatred for one another goes back over 2000 years, when the city was split by those fighting for and against Rome in the Second Punic War (218-201BC).
29. Colo-Colo vs Universidad de Chile
Another rivalry swamped in history. Universidad fans taunt Colo-Colo by calling their home the 'Pinochet Stadium', amid controversy over the notorious dictator allegedly funding the ground.
28. Benfica vs Sporting
Sporting started out poaching Benfica's players and it soon became about wealth and class, with Benfica begrudging their rivals being funded by founder Jose Alvalade.
27. Hajduk Split vs Dinamo Zagreb
About as much of a local derby as Brighton and Crystal Palace (which is equally venomous in its own way). They represent the two biggest cities in Croatia and have dubbed it the 'Eternal Derby'.
26. Raja vs Wydad
A prime example of when derbies can go too far. Located in Casablanca, there have been several unsavoury incidents, including a fan being killed in 2007. That led to a behind-closed-doors ban. Just three years later, over 100 people were arrested in a riot.
25. Real Betis vs Sevilla
Sevilla have undoubtedly been the more successful of the two clubs but Betis have stayed true to their blue-collar roots in a rivalry that started as a clash of the classes.
24. Newcastle United vs Sunderland
What makes the Tyne-Wear derby so special is that these are both 'one-club' cities. The whole of the north-east gets involved and some Newcastle fans even take it as far as refusing to eat bacon because of its red and white stripes...
23. Corinthians vs Palmeiras
A bystander lost their life in 2016 amid running conflict between the two sets of fans. Sao Paulo plays host to one of the most intense rivalries in South America.
22. Partizan Belgrade vs Red Star Belgrade
Both their names bear the connotations of post-war Communist Yugoslavia. They both became symbols of power during the Balkan conflict of the 1990s, when Red Star's 'Delije' also became engaged in open warfare with Dinamo Zagreb's Bad Blue Boys.
21. East Bengal vs Mohun Bagan
Mohun Bagan are India's oldest club. East Bengal, on the other hand, were born as a breakaway from the original side and soon became associated with the separatist movements of what's become Bangladesh.
20. Arsenal vs Tottenham
You very rarely get a *bad* North London Derby. Spurs went eight years without winning one before winning 5-1 at White Hart Lane in 2008. In recent years, the Lilywhites have overseen a power shift in the north of the capital but these games are still usually close, and brilliant, watches.
19. Olympiacos vs Panathinaikos
No other side has won the title in Greece since 1997. When they get together, it's known as the 'Mother of All Battles'.
18. Flamengo vs Fluminense
Legend has it that Fluminense were once so desperate to win that after taking the lead, they began deliberately kicking clearances into the nearby lagoon, with Flamengo players having to wade through the water to get the ball. As many as 194,000 have rocked up to the Maracana for this famous fixture.
17. FK Velez vs HSK Zrinjski
The Neretva River and the famous bridge divide Mostar, with Velez largely enjoying support from the Muslim community and Zirnjski remaining a symbol of Croat nationalism.
16. Ajax vs Feyenoord
You have to be a brave man to cross the divide as Johan Cruyff did when Ajax failed to offer him a new deal. The two clubs have always been polar opposites. Liberal Amsterdam vs industrial Rotterdam and the politics associated with the two cities make this a derby about far more than football.
15. Independiente vs Racing Club
The 'best of the rest' after River Plate and Boca Juniors, these two clubs are just 300 metres apart from one another, a proximity that has leant itself to plenty of riots down the years.
14. Portsmouth vs Southampton
Portsmouth's sad demise means this is a rivalry we rarely see much of nowadays. They were reunited for the first time in seven years in 2019 and unsurprisingly, the Saints ran out 4-0 winners in the League Cup.
13. AC Milan vs Inter
Inter were formed during a split over signing foreign players among the Milan Cricket and Football Club. They have had a rivalry ever since, though ultras made a pact to lessen the violence when a supporter sadly died in 1983. And, of course, they share the beautiful San Siro.
12. Chivas Guadalajara vs Club America
Mexico's biggest clubs who bear very different philosophies. Chivas are all about developing homegrown talent, while America like to buy big from overseas.
11. Marseille vs Paris Saint-Germain
It lacks the history of some derbies as PSG were only formed in 1949. Inevitably, in recent years it's been the Parisians who have had the greater joy.
10. Ah Ahly vs Zamalek
Over 50 million people watch the fixture in Egypt, Al Ahly having come to represent national independence and Zamalek celebrating the mixture of Egyptians and Europeans playing together.
9. Borussia Dortmund vs Schalke
Imagine attending the Schalke game in Dortmund's famous Yellow Wall. At its fiercest in the 1970s, the economic problems of the era in the Ruhr region saw fans turn ever more towards football as an escape.
8. Gremio vs Internacional
Over in Brazil, Gremio was initially a members' club who only welcomed those of German ancestry. That led a group of brothers of Italian descent into forming Internacional - hence the name.
7. Liverpool vs Manchester United
English football's two greatest power houses. They've interchangeably fallen from grace in recent years but Liverpool's resurgence now means it's a vital date in the calendar once again. Even if they both have their own local derbies, it' still the biggest fixture in the Premier League.
6. Fenerbahce vs Galatasaray
They may have gained notoriety for their welcomes in the Champions League and it's no different in Turkish football. Technically speaking, this is an inter-continental rivalry, with Galatasaray in Europe and Fenerbahce in Asia.
5. Lazio vs Roma
Paolo Di Canio once claimed these two sets of fans care more about winning this game than they do where they eventually end up in Serie A. The displays ahead of kick-off really are something to behold.
4. Nacional vs Penarol
These are the oldest club rivals outside the UK and they've been putting on vitriolic derbies full of colour for over a century.
3. Celtic vs Rangers
Another affair as much about religion and politics as football, the latter is finally proving equally important again now that Rangers have returned to start challenging the Hoops for major honours. Bottles, cans and alcohol are all banned.
2. Barcelona vs Real Madrid
El Clásico has played home to some of the greatest footballers of all time. That has often meant huge stakes to play for and the enmity between the two was summed up when Luis Figo had a pig's head thrown at him after crossing the divide.
1. Boca Juniors vs River Plate
Boca-River has always been about social class. Now, more than ever, it's also just about pure, footballing hatred itself and has to be policed by over 2,000 officers.
There are definitely more than enough derbies for the bucket list here.
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