Former Manchester United defender Gary Neville says it was always the plan to change kits at half-time against Southampton in 1996.
United found themselves 3-0 down to the Saints at The Dell in the 1995/96 Premier League season after suffering a number of poor results in their grey kit that season.
The Red Devils ended up limiting the damage to just a 3-1 loss and Neville claims there was a degree of "science" behind Ferguson's choice to change the kit at the break.
Speaking on Sky Sports, Neville said: "There was a little bit of science behind it. Sir Alex had employed Gail Stephenson a couple of years before from Liverpool University, I think she was at the time. And we had Gail at the time, believe it or not, as our eye coach.
"It sounds really daft this but one of the great theories around football that was presented at United at the time was that match sharpness was nothing to do with your physical fitness. It was to do with your eye muscles being able to react to things that happened on a football pitch.
"You are getting back to match sharpness wasn’t to do with physical, it was actually the ability to pick up the things that happened in a game quickly.
"I had a bigger problem with The Dell just generally. As much as Matt [Le Tissier] loved it, we hated it. Maybe not the previous Manchester United players who had a good record there but when we came into the squad The Dell on a sunny day was just awful for us.
"It just did not feel comfortable for us at all, it was something that when Southampton moved to St Mary’s it was so much better for us.
"Going back to the vision story. Sir Alex had basically been told by Gail that the colours that you can spot most easily that grey was the worst possible in terms of the fans in the background.
"So, he had it in his head basically the players couldn't see each other as well because of this kit. He believed in his coaching staff and Gail was our eye coach and we used to do eye exercises before every game. I did them for 20 years, believe it or not, even though I struggled to pick out my players when they were in red shirts.
"There was a little bit of science behind it even though it didn't look particularly good to the outsider that we changed our kit at half-time.
"Think about this, why would we have another kit ready? He had this in his head before the game that the kit was a problem because he’d been told by Gail. And we had a full set of shirts ready to put on at half-time. You don’t take a different set of coloured shirts to a game unless you’re thinking there's a problem with it."
- TEAMtalk media