Everton boss Roberto Martinez has admitted the club are powerless to prevent star winger Gerard Deulofeu from joining Barcelona should the Catalan giants want him back at the Camp Nou next season.
Deulofeu, a Barca youth product, has been a revelation for Martinez's men this season, recording a goal and five assists in 10 Premier League appearances thus far.
The La Liga club sold Deulofeu to Everton just this summer, but inserted a buy-back clause in the deal which would allow them to re-sign the 21-year-old at the end of the campaign.
Speaking on Thursday, Martinez revealed the arrangement was the only way to bring Deulofeu to Goodison Park, and that he was happy with the deal.
"There is nothing we can do if they activate it," Martinez said. "That was the deal and the only way we could access the player in the terms that we wanted.
"I'm delighted with the deal.
"They can't sell him on at a higher price. There are certain things in the deal.
"They can't take him back in the winter so they can't take him back in January. It can only be at the end of the season.
"If they take him back, they can't sell him for a season. So he has to stay in the first team squad for a season.
"At the end of that, if they decide to sell him, we have got first rights of getting him back, or we have got a big percentage of that."
Martinez hailed the Spaniard's standout performance in Everton's 1-1 draw at West Ham on Nov. 7, after which Deulofeu scored five goals in two games for Spain's under-21s.
"He has gone to a different level," Martinez said of Deulofeu. "If I showed you the stats against West Ham, you wouldn't believe them. He had more high intensity off the ball than on it.
"That is the first time ever since he has been in professional football.
"I'm not worried about it, though. My worry would be to lose him in January.
"For us to have him, a quality player, for the money that we paid, if we lose him it will be on a profit financially so we would be able to use the money.
"You're talking about a Barcelona player who has been all through his years as the golden boy believing he is going to be at the top level at Barcelona and we got him for a very good price."