Vieira called United his ­"favourite enemy". In his first season in ­England he witnessed Ian Wright having to be restrained from thumping Peter ­Schmeichel by police and a subsequent ding-dong in the tunnel. His most maddening flare-up occurred in 2003 when he was sent off at Old Trafford for aiming a retaliatory kick at Ruud van Nistelrooy, who had stamped on him. Despite the lack of contact the Dutchman writhed around until the red card was ­flourished. "Personally, I can't stand the sight of Van Nistelrooy," wrote Vieira in his auto­biography. "Everything about him annoys me. He's always ­complaining, whingeing. The man is a cheat and a coward. Everyone thinks he's a nice guy but in fact he's a son of a bitch."

It is almost impossible to imagine many of the current line-ups getting as steamed up about a direct opponent from this fixture. A frisson of ­anti‑Arsenal feeling lurks in Wayne Rooney, but not to compare to the buttons pressed by Liverpool. Cesc Fábregas remembers the last volcanic eruption at Old Trafford in 2004, when ill will was manifested in the so-called "battle of the buffet" as an angry upstart aimed a pizza at Sir Alex, but a run of uncontroversial encounters has turned down the electricity.

It all began way back in 1987, coincidentally Sir Alex's first appointment with Arsenal since he arrived at Old Trafford from Aberdeen. "I'll never forget our first exchange, when United beat us at Old Trafford in 1987," recalls George Graham, Arsenal's manager at the time. "David O'Leary was getting kicked all over the place by Norman Whiteside, David Rocastle was provoked so much that he got sent off and there was a big row coming off the pitch. Alex Ferguson and his then assistant Archie Knox were right in our faces and I thought: 'Jesus Christ! That'll be the first and last time they intimidate us. We're not going to be bullied any more'."

A year later Brian McClair missed a penalty in the last seconds of an FA Cup tie at Highbury and Nigel ­Winterburn followed him back to the centre ­circle to throw some bullying back by ­antagonising him all the way with unforgettable pleasantries.

The first act of the United-Arsenal enmity came to a climax on 20 ­October 1990 as McClair took his revenge on ­Winterburn, laying into the full-back after he had launched a tackle late enough to be registered the following week. That sparked a 21-man scuffle. As the late David Rocastle described it: "It was our team-mate, our little blood brother, in trouble. They were kicking Nigel like a nightclub brawl. That's what got us upset. If it was just a bad tackle, you wouldn't go in like that, no chance. But when I saw them kicking Nigel I ran over thinking, 'You can't have this'! We went in there and we stuck up for each other. At Arsenal we never, ever started any brawls – we just finished them."