Magistrates agreed with the Manchester United manager's defence that it was an "emergency," and they cleared the 57-year-old.

Bury Magistrates Court had been told that Sir Alex had been suffering from severe diarrhoea when the incident took place on 26 February on the M602, in Eccles, Greater Manchester.

He said his symptoms had begun at home the previous day. He had been to see the club doctor, Mike Stone, the following morning at Old Trafford, and felt much better after taking Imodium tablets.

Stomach cramps

But on his journey home he was struck by stomach cramps and the urgent need to visit the lavatory.

The M602 at Eccles was congested, he told the court, and to avoid queuing, he drove his BMW onto the hard shoulder.

He was followed by a police vehicle, stopped and cautioned. He told the court that he was too embarrassed to explain his predicament to the police officer.

Sir Alex was "in a rush" to use Old Trafford's facilities

"When I got on the M602 I started to feel the cramps again," Sir Alex told the court.

"When I got into the snarl-up of traffic I took another [Imodium] tablet. I stayed there for about four or five minutes. I then decided to try and get back to Old Trafford."

Nicholas Freeman, defending, said: "Putting it bluntly, did you need to go to the toilet?"

Sir Alex said: "That was very much the case. I had to go somewhere quickly."

After giving his details to the police Sir Alex returned to Old Trafford to use its facilities. "I was in a rush," he told the court.

'Acute gastroenteritis'

In a statement to the court, Dr Stone said: "I saw Sir Alex at 9am on 26 February when he complained of suffering from severe diarrhoea.

"I examined him and diagnosed acute gastroenteritis."

Mr Freeman said his client had had two options while in the traffic jam.

"One is unthinkable and one is to take evasive action," he said.

"It's not easy for someone in his position to come into court and, with respect, explain his toilet difficulties on that day," he added.