Brian Kidd used to play for Manchester City and has worked for the Citizens as a coach since 2009.
However, the 66-year-old also played for Manchester United. He scored in the 1968 European Cup final against Benfica and was employed as a coach at Old Trafford between 1988 and 1998.
Subsequently, Kidd and Ryan Giggs know each other very well - and after being hit in the back with a bag of balls in the tunnel before the Manchester derby on Sunday, Kidd might have guessed that Giggsy was responsible. (Scroll down this page to watch the video).
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Giggs was walking down the tunnel towards the pitch with a bag of balls when he spotted Kidd standing near the media.
The Welshman walked up behind the unsuspecting Man City coach before hitting him in the back.
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Kidd, after noticing who it was, said to Giggs: “Oi. We were just talking about you!”
United’s assistant manager looked around but didn’t stop to find out why.
Video: Ryan Giggs trolls Brian Kidd
Skip to 4 mins, 40 seconds...
The tunnel cam video from Sunday certainly makes for interesting viewing.
Louis van Gaal looked very tense prior to the match but ended up sealing one of the biggest victories of his Manchester United tenure.
Few expected United would win at the Etihad Stadium, but win they did thanks to a first-half goal from the impressive teenager Marcus Rashford.
The Red Devils now sit one point behind fourth-placed Manchester City and are only behind fifth-placed West Ham by virtue of their slightly inferior goal difference.
Van Gaal determined to secure top-four finish
A delighted Van Gaal told reporters after the match that his team now have a “big chance” of securing Champions League qualification.
"The gap would have been too big if we had drawn or lost. It would have been very difficult," the veteran Dutch coach was quoted as saying by BBC Sport.
"Now it is in our own hands but we have to win our games. We have more home matches than away and we don't lose so much at Old Trafford - so we have a big chance."
Van Gaal added: ”I thought we played fantastic in the first half and the second half was a test of survival because we were very tired.
"We had only two days to recover after the Liverpool game and that is almost not possible.
"We have seen the result from Southampton today. Liverpool were 2-0 up at half-time and at full-time it was 3-2 to Southampton.
"I have not seen the match but I can only conclude it was because of tiredness and that is what we have done to them."
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