The Germany international moved to Real Madrid from Bayern Munich on a six-year deal in July after helping his country win the World Cup in Brazil.
Madrid, Bayern, Barcelona and Chelsea are the four biggest clubs at the moment
Kroos, 24, was heavily linked with a transfer to Old Trafford before his eventual switch to the Bernabeu.
But the midfielder says that he would have preferred a move to Stamford Bridge – because he rates the Blues as one of the top four clubs in the world.
“I’m happy to have been given the chance to try something new,” Kroos told Die Welt. “Even though it’s only been a short while I feel like it was the right decision.
“Madrid is a special club and the challenge I was looking for after my long and successful career at Bayern.
“Madrid, Bayern, Barcelona and Chelsea are the four biggest clubs at the moment, so I would only have swapped one for another.”
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