After taking charge of his beloved Manchester United on a caretaker basis following the dismissal of David Moyes, Giggs became assistant manager to the Dutchman when he took the reins in 2014.
Van Gaal was entertaining in his press conferences and interviews but the football from his side was far from it and he was sacked two years on despite guiding the club to an FA Cup win.
Giggs, who spent pretty much the whole of his professional career playing under Sir Alex Ferguson, found the former Barcelona boss to be "dominating" and "quirky" and recalled his bizarre first meeting with him.
"He was different. He was very dominating," Giggs said on Jamie Carragher's Greatest Game podcast.
"The first time I met him he punched me in the stomach.
"I've gone to meet him, we've got a list of players that I think were good and the ones that were not so good.
"I've gone to meet him a hotel, he's opened the door, looked me up and down and gone 'you are in good shape!' then he punched me in the stomach.
"It was hard as well and I didn't know what to do. You could have given something back but that's me out of a job.
"But that's what he was like. He was very dominating and would be right up in your face.
"He would be a nightmare now with social distancing. He would be right up in your face, looking down on you and very direct.
"He looked after his staff and players and he was a really good person but just very quirky."
Jose Mourinho replaced Van Gaal in the Old Trafford hotseat and Giggs was not kept on the backroom staff.
He's been manager of the Wales national team since 2018 and although he has ambitions to go into club management, he thinks the dream job of taking charge at United has gone.
"I'm happy with the job I've got," Giggs stated.
"I can't see that (Man United) coming around again. I must say I'm enjoying the Wales job at the moment. There's lots of pluses, and there's lots of frustrations. I think eventually I will want to go into club management, but when that is, I don't know."
Featured Image Credit: PA
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