With the Manchester derby just days away, we take a look at some of the fiercest rivalries in world football. Here, in part one, we travel to Serbia, Scotland, Sao Paulo, Rome and Istanbul.
Partizan Belgrade v Red Star Belgrade (Belgrade, Serbia)
The Balkans is a renowned hotbed of fierce football rivalry yet nothing in the region compares to the biannual battle of Belgrade.
Known as the Eternal Derby it is a rivalry that both unites and divides the entire Serbian nation with allegiances being formed from birth.
The rivalry is such that it is not uncommon for the first gift to a baby to carry either a Red Star or Partizan emblem.
And such are the fierce passions engendered, it is a derby that sadly has prompted outbreaks of violence on numerous occasions down the years.
It also goes beyond mere football with both teams having nearly 20 other sporting franchises bearing their respective names, most notably basketball as well as handball and volleyball, where the sparks also invariably fly.
Both sides were formed in 1945 after World War Two in the fledgling Yugoslavia with Partizan founded by the military and Red Star set up by some members of the police force.
And despite the subsequent political and social upheaval across the Balkans – and tragic conflicts that marked the break-up of the Yugoslav republic almost 30 years - one thing has remained constant.
It’s a grudge match that brings that whole of the region to a virtual standstill.
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Rangers v Celtic (Glasgow, Scotland)
For many, Scotland’s Old Firm rivalry remains the very essence of derby tribalism, representing the ultimate in footballing division.
It’s one of the oldest and most complex rivalries in world football, with its roots lying in religion and identity as much as the battle for footballing supremacy.
Celtic were founded in 1887 by a Marist (Catholic) Brother from Ireland and the club's origins were firmly embedded in Irish Catholicism.
Rangers, meanwhile, founded in 1872, became the team of the Scottish Protestant working class almost by accident.
Ironically, relations between the two clubs were initially friendly, with Rangers supplying the opposition for their neighbours' first game.
However, the opening of a huge shipyard in Govan, just a short walk from Rangers' Ibrox home, by industrial firm Harland and Wolff, saw an influx of Protestant workers from Belfast in the 1910s. The company's infamous "Catholics need not apply" policy soon spread to the club their workforce adopted.
The clubs' identities were subsequently shaped in direct opposition to each other, with Celtic associated with socialism and Irish Republicanism, Rangers with conservatism and Northern Irish unionism.
Between them, the two Glasgow giants have largely dominated the Scottish game, winning more than 100 league titles between them and that battle for domestic supremacy has only fanned the flames of bitterness and bad feeling which surround the fixture.
Not surprisingly, the rancour and division has frequently led to trouble on and off the pitch with a notorious pitch invasion and on-field trouble at Hampden Park after the 1980 Scottish Cup final being instrumental in the subsequent imposition of a ban on alcohol at Scottish grounds.
Former Celtic star Henrik Larsson and ex-Rangers forward Brian Laudrup both claimed the Old Firm rivalry topped anything else they had experienced in their careers – including El Clasico and the Milan derby.
Corinthians v Palmeiras (Sao Paulo, Brazil)
Rio de Janiero may be the capital of Brazil but arguably the country’s most intense derby rivalry is that of Sao Paulo rivals Corinthians and Palmeiras.
Such is the scale of Sao Paulo, the city also is home to Sao Paulo FC with a fourth, Santos, based a short distance away.
However, it is the animosity between Corinthians and Palmeiras that fuels the passions in this football-mad country like no other.
Both derived from working-class backgrounds, Corinthians take their origins from a tour to the city of English side Corinthian FC in 1910 which inspired local labourers to form their own club, Sport Club Corinthians Paulista.
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Four years later a group of Italian factory workers followed suit following an exhibition tour by Italian clubs Torino and Pro Vercelli out of which formed Palestra Italia, later changed to Palmeiras.
Part of the intense rivalry stems from the fact that legend has it that it was ex-Corinthians members who helped found the club.
The two teams share similar records, one Copa Libertadores each, eight Brazilian titles for Palmeiras to six for Corinthians which has only fed the sense of competition and rivalry – both on and off the field.
Indeed, in the past, trouble between rival fans has seen respective fan clubs outlawed by a Sao Paulo court and it’s a fixture that still carries a hold over Brazil like no other.
Lazio v Roma (Rome, Italy)
The Roman derby or Derby della Capitale eclipses all other Italian intra-city derbies. The only fixture in our 10 to take place in a shared stadium – the Stadio Olimpico – it has established a reputation for being one of the most fiercely-contested matches throughout all Europe.
The formation of Roma came about in 1927 when they were created, due in part to Fascist Dictator Benito Mussolini’s desire to end the dominance of the teams from the north. Three teams, Roman, Alba-Audace and Fortitudo were bonded together to form AS Roma.
One existing team in Rome though refused to unite - SS Lazio and so the seeds of the bitter rivalry began.
While the rival Milan clubs, Inter and AC along with Juventus have traditionally been Italy’s most successful clubs, for Roma and Lazio more often than not it’s all about the derby.
Sadly, over the past few decades, the fixtured has been marked by fighting, racist abuse, anti-semitic banners, riots and death.
In 1979 a Lazio supporter was hit in the eye with a flare thrown by a Roma fan and became the first fatality due to violence in the history of Italian football.
Roma ultras also forced the suspension of a game in 2004 when false rumours of a child being killed by police before the match caused chaos.
These days such is the ongoing menace surrounding the fixture the Roman police have insisted on a daylight kick-off for security reasons.
Fenerbahçe v Galatasaray (Istanbul, Turkey)
One of the great cities of the world, Istanbul is also home to one of football’s most intense and frenzied rivalries.
The enmity is drawn from both geography and class with the clubs originating from two different sides of the Bosphorus which dominates the city.
Fenerbahçe SK were founded in Kadıköy, the Asian side of Istanbul, while Galatasaray SK were founded in Galatasaray, which sits within the city’s European side.
As such Gala are seen by many as a club for the aristocracy, while Fener are considered the “people’s club” with a working-class background though that social divide has narrowed in recent decades.
One thing that has only intensified however is the needle over what is known as the Inter-Continental derby or the Eternal Rivalry.
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The tinder-box tone was set in 1934 when an Istanbul derby had to be abandoned after a fight broke out between the opposing teams.
But for many the passions the game inflames is best personified by the infamous incident in 1996 when Graeme Souness, the then-manager of Galatasaray, almost sparked a riot by planting his club’s flag in the centre of the Fenerbahce pitch after Gala had beaten their bitter rivals on their bitter rivals’ turf in the Turkish Cup final.
The enmity still runs deep.
Only last week, the latest clash between the teams – a 2-2 draw – ended in scenes of mayhem as three players were sent off after the final whistle following a brawl that embroiled 30 players and staff.