Barcelona have re-signed winger Gerard Deulofeu from Everton after exercising a buy-back clause believed to be worth 12m euros (£10.6m).
Deulofeu originally went on loan to Everton in 2013-14 then signed in a £4.3m permanent deal in 2015.
The 23-year-old made 13 appearances for Everton last season before joining AC Milan on loan in January.
The Spaniard, who came through the youth academy at the Nou Camp, has signed a two-year deal.
After a good first season on Merseyside, Deulofeu fell out of favour and manager Ronald Koeman allowed him to spend the second half of the last campaign in Italy.
He started 36 games for Everton, with a further 39 from the bench, scoring eight goals. His contract had been due to run until June 2018.
Deulofeu said: "I am very happy to have returned home and cannot wait to start this project. I have always wanted to be here.
"I have had to work away from Barca, because it is not easy to get into the first team, but I have come here with a lot of desire.
"I have changed a lot, I have had different experiences and I think I have improved as a person and a player. I am a different player and I am going to try and help the team.
"I know that competition is high, but I will work hard every day and I am going to try and learn from the best to help the team to win titles."
Phil McNulty, BBC Sport's chief football writer
Deulofeu's departure from Everton is no surprise as he was clearly not part of Ronald Koeman's plans. The only thing that might seem surprising is that he returns to Barcelona.
He had been sent out on loan by Barcelona to Everton and Sevilla with mixed results before he made a permanent move to Goodison Park in June 2015.
Deulofeu was regarded as talented but wildly inconsistent, a status he has done little to alter in recent times, including during a loan spell at AC Milan last season.
Barcelona, however, clearly believe the raw materials are there - which they undoubtedly are - and that new coach Ernesto Valverde can fashion the finished product.
However Deulofeu faces a challenge to secure regular game time - given Barcelona's attacking riches include Lionel Messi, Luis Suarez and Neymar - at what is the crucial phase of his career.
He is a player who can excite and exasperate in equal measure. Deulofeu must now alter that balance in his and Barcelona's favour.
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