Ousmane Dembele has been presented as a Barcelona player after completing the formalities on his move from Borussia Dortmund.
The clubs announced agreement had been reached on a £97m deal on Sunday and Dembele completed his medical on Monday afternoon in the Catalan city.
There was a brief delay, with almost 20,000 fans waiting around for a couple of extra hours, before the 20-year-old appeared alongside Barcelona president Josep Maria Bartomeu to put pen-to-paper on a five-year contract.
"I'm really pleased to form part of the Barca family," Dembele said after signing a deal that could eventually earn the Bundesliga side nearly £135m.
"I have always wanted to play for Barca since I was a kid. I watched all their matches.
"I'm really happy to now be part of the best club in the world with the best players in the world.
"I hope to win lots of trophies and titles here. I'm hoping forward to a good year, a successful year and looking forward to playing here in this stadium."
The forward's transfer is the second highest of all time, just behind the £200m Paris Saint-Germain paid Barcelona for Neymar earlier this summer.
Dembele joined Borussia Dortmund for £13m from French side Rennes last summer and went on to score 10 goals in 50 appearances in his debut season at the Westfalenstadion.
He could make his Barcelona debut after the international break with Ernesto Valverde's men facing city rivals Espanyol in their next La Liga game on September 9.
Dortmund have signed Dynamo Kiev playmaker Andriy Yarmolenko as Dembele's replacement, paying £23m for the Ukraine international.