Thirty-one years of animosity provides the background for tonight's Worthington Cup tie between Chelsea and Leeds United at Elland Road.
The antipathy between players and supporters is a legacy of a bitter FA Cup Final which was played before most of this evening's protagonists were born.
|Jack Charlton: There at the start of the Chelsea feud|
The 1970 Cup Final was one of the most physical ever contested, and that in an era when football was a good deal more basic than the refined brand served up in today's Premiership.
There was already history between the teams. Don Revie's Yorkshire hard-men were famous for their elastic approach to the laws of the game with committed players like Billy Bremner, Jack Charlton, Johnny Giles and Norman Hunter.
Dave Sexton's Chelsea, while having a reputation for flair and panache, also had a team populated with men who who didn't mind a bit of afters; men like Chopper Harris, Dave Webb and Peter Osgood.
The first match was played on a Wembley pitch that had been churned into a quagmire by the Horse of the Year show.
The game was an attritional slog, but Leeds were widely seen as the better team, and Chelsea were lucky to get a 2-2 draw.
The replay at Old Trafford descended into football barbarism. Leeds scored first through Mick Jones, but Osgood's equaliser opened the floodgates of foul play.
Peter Lorimer, the Leeds midfielder, said: 'Jack Charlton let in Peter Osgood for them to score and that fired them up.
'They came out for the second half and kicked everything above grass.'
Chelsea would argue that they were only meeting fire with fire, but their tactics worked. Webb, who had been humiliated by Leeds' left-winger Eddie Gray at Wembley, bundled in an extra-time winner and the Cup went to Stamford Bridge for the first time.
Years later, the respected Premiership official David Elleray 'refereed' the replay again on video. The real ref on the night, Eric Jennings, somehow saw fit only to book one player, Chelsea's Ian Hutchinson.
Applying modern standards, Elleray saw it rather differently. By his count, Leeds should have had seven bookings and three sent off (Giles, Bremner and Charlton).
Elleray reckoned Chelsea deserved 13 bookings, including three each for Webb, Harris and Charlie Cooke who, of course, would all have ended up down the tunnel long before the final whistle.
The match provided a lengthy sheet of misdemeanours.
Chelsea's hard-men systematically targeted Gray, and Webb should have gone off inside 13 minutes for a series of fouls on the Scot.
Harris finally nailed Gray late in the first half with a malicious kick on the back of the left knee. Gray collapsed and was a passenger for the rest of the game. Harris should have walked.
Moments later, Charlton head-butted and kneed Osgood after the Chelsea striker had tackled him from behind.
Wherever you looked on the field there was mayhem, as players kicked, gouged and butted each other with impunity.
The next morning, one paper summed up Chelsea's triumph with the banner headline: 'Robbery with violence.'
Though most neutrals wanted Chelsea to win, some ended up feeling a little pity for Leeds. After all, Revie's side had led three times, only to be pegged back on every occasion, finally losing it in extra-time after 240 minutes of hard slog.
It was probably the last time anyone ever felt any sympathy for the Yorkshire club and small wonder Chelsea resented their bad press.
After all, they were only playing Leeds at the game they had perfected: the game of rule-bending and intimidation.
Not many other sides of the era had Chelsea's relish for the battle.
The ill-feeling simmered on throughout the Seventies, and there were always fireworks when the two teams clashed.
But despite the memory of that bitter combat, it's highly unlikely that tonight's encounter will generate such levels of hatred. We're unlikely to see half-a-dozen red cards.
That's the problem with footballers these days. No sense of history.
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