It was probably a good job that the decision to rule out Manchester United’s legitimate goal from an ingenious corner against Chelsea at Old Trafford yesterday ultimately had no bearing on the result, because one could only have imagined how Sir Alex Ferguson might have reacted had it proved pivotal rather than an intriguing postscript.

When Wayne Rooney rolled a foot over the ball after placing it on the corner arc shortly before half-time, no one reacted, presumably in the belief that he was leaving the kick for Ryan Giggs to take.

In reality, the ball was active and, after Rooney whispered to Giggs that he had taken the corner as the pair passed each other, the Welshman collected the ball and darted towards goal before crossing for Cristiano Ronaldo to score with a header.

Darren Cann, Howard Webb’s assistant, raised his flag almost the moment Giggs collected the ball and the “goal” was ruled out. The officials explained that the goal was disallowed because Rooney did not tell Cann of his plans. But United would not have been able to inform the assistant referee had the corner been on the opposite side, unless a player ran across the pitch to tell him.

Ferguson said that it was a tactic the players had practised, although they are not the first to try it. Roma did the same against AC Milan last season. “Luckily we scored just after it, because we would have been a bit annoyed if we hadn’t done,” Giggs said.

Ferguson questioned the legitimacy of the claim that Rooney would have had to inform the referee’s assistant of the move for the goal to have stood. Rooney added: “The linesman’s got it wrong today.”