Chelsea have signed Benfica midfielder Ramires on a four-year contract.
The Premier League champions had been in negotiations with Benfica for more than two weeks over the transfer of the 23-year-old, for a fee believed to be in the region of £17 million.
Ramires underwent a medical on Sunday but completion of the deal was held up due to work permit problems as the Brazilian had not played the required 75% of matches for his country. The former Cruzeiro player was granted the required documentation on appeal on Friday.
Former Cruzeiro player Ramires will miss the opening Premier League game against West Brom and instead join up with his new colleagues next week.
"Every player in the world would love to play for Chelsea and it's a great opportunity that was given to me, I will give my best to repay this chance, and I am very happy,'' he told the club's official website.
Blues boss Carlo Ancelotti said: "He is a fantastic player, a fantastic midfielder, he is very young and will be the future of the Brazilian national team, and I hope he will be the future of Chelsea.''