Barcelona confirmed the signing of Danish forward Martin Braithwaite from Leganes after capitalising on a curious La Liga rule to ease their shortage of options up front.
Barca have taken advantage of the regulation that enables Spanish clubs in the top two divisions to buy from another La Liga club outside the transfer window if they lose a player to injury for more than five months.
"My ambition has always been to play at this level and when you persevere and you are positive, things end up happening," said Braithwaite after signing his contract on Thursday.
"I am very happy to be here because, as a footballer, it is one of the greatest things that can happen to you to play for the best club in the world."
However, Barca president Josep Bartomeu insisted: "Barcelona's attitude has been correct."
"We paid the clause in accordance with the regulations, but we think it should be revised because it is not fair that Leganes cannot therefore recruit."