Porto have already replaced Manchester City-bound Eliaquim Mangala.
The French international's departure from the Estadio do Dragao was confirmed this morning, with Porto believed to have received £32m from their Premier League counterparts for the 23-year-old.
Some of those funds have now be reinvested with the signing of Ivan Marcano for an undisclosed fee from Russian club Rubin Kazan.
"I am happy and proud to be in a club like FC Porto, with a history full of titles and truly amazing fans, the best in football nowadays. I know what is expected of me and I am ready to help the team get back to winning titles," the 27-year-old told the club's official website.
The former Spanish youth international, who has agreed a four-year contract, spent last season on loan with Olympiacos.
