United eventually gave in and agreed to pay Sporting a fee which could rise to £67.8million with add-ons to land their captain just before deadline day last month.
"I realised in the negotiations that Manchester United was convinced that we were going to give in and that for 50 million euros he was doing the deal. Well, they ended up paying 65 million," Zenha told Record.
"They were wrong and ended up paying what we wanted. We went to get 20 million more than if we had sold four months ago."