The ex-Argentina international arrived at Old Trafford in 2001 for a hefty fee of £28million.
In west London, Veron found it even tougher, especially with his family, and he subsequently spent just one season with the Blues.
Juan Sebastian Veron failed to justify his £28m fee at Manchester United
The intense and clogged fixture schedule in England was a major disruption for the 41-year-old.
And Veron blames the Christmas period for ruining his form at Manchester United, causing him injuries.
“I don’t make excuses,” Veron told FourFourTwo. “It was a new thing for me, even if I’ve always faced change with ease. My family was happy, I was happy.
“The real change was the physical aspect. I regard fitness training as a very important thing.
Juan Sebastian Veron recently came out of retirement to play for boyhood club Estudiantes
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“I moved from a country with intense pre-season training to another where football matches are the only way they train. In England they play the whole year: Christmas, New Year, non-stop.
“The first six months I coped with it well – really well. But after December, it was very difficult for me to keep up. I would suffer from the lack of a fitness base, I wouldn’t be able to last the whole game, and I would pick up injuries.”
After being warned by Sir Alex Ferguson he may lose his place in the United team, Veron decided to start again with Chelsea.
Veron made just 14 competitive first-team appearances for Chelsea
I should have stayed in Manchester. My wife left Manchester in tears
Juan Sebastian Veron
But the switch made matters worse on and off the field.
Veron added: “Looking back, I didn’t make the right choice. I should have stayed in Manchester. My wife left Manchester in tears. We were used to moving cities and I’d never seen her crying because of a move.
“I had talked to Ferguson and he had told me that he couldn’t guarantee my spot in the team; that I had to earn it. And it was logical. I didn’t think it through.”