"Barcelona had an issue with signing Marcus initially, which was the club’s financial situation. But they also thought United were playing a game because they were willing to let him go," a source told The Sun.
"They thought it was too good to be true - there must be something wrong with him. His brother Dwaine persuaded them there was nothing wrong - and that he wasn’t going to mess them about. Barca are now really shocked that they could sign him for what they see as a bargain."
It has been revealed that Barca manager Hansi Flick urged the club’s sporting director Deco to sign Rashford last summer.
"I told Deco in the summer, ‘Bring me Rashford, bring me Rashford, please’. We needed a player like him," said Flick.