The Premier League giants both wanted to lure Neymar to England from Santos.
Rosell revealed: "I spoke with his father when we met in Miami and we closed the deal there.
"There were four parties that owned his rights as part of the agreement and we had to agree with all of those, but in the end we closed the deal for €57.5m (£48.6m).
"The key was that the player wanted to come to Barcelona.
"Everything was based on that despite offers he had from Man City, Chelsea, Bayern and Real Madrid."
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