Dembele presentation doesn't go to plan for Barca

The 20-year-old became the second most expensive player ever after completing a 105 million euro ($125 million) deal that could rise to 147 million with add-ons from Borussia Dortmund on Friday.

However, Barca's planned programme for a blockbuster presentation was delayed for nearly two hours due to a paperwork issue in releasing his registration from Dortmund.

The patience of 18,000 fans at the Camp Nou was tested with whistles during the delay and chants of "Bartomeu resign".

Barca's board has been under huge pressure due to the club's fading fortunes on the field and the loss of Neymar to Paris Saint-Germain for a world record 222 million euros earlier this month.

The attendance was also well down on the 50,000 fans that welcomed Neymar on his presentation four years ago.

Following Barca's recent 5-1 aggregate thrashing by Real Madrid in the Spanish Super Cup, the hashtag "bartomeudimiteya" (Bartomeu resign now) became a trending topic worldwide on Twitter.

Dembele finally emerged in Barca's famous red and blue strip, sporting the number 11 jersey vacated by Neymar.

"I am very happy to be a part of this club," Dembele told the fans.

"It is the best club in the world with the best players in the world." 

Dembele will form a fearsome forward line alongside five-time World Player of the Year Lionel Messi and Luis Suarez as Barca aim to wrestle the Champions League and La Liga titles back from rivals Madrid.

"I hope we'll have a great season and win all the titles with Barca," added Dembele.

"I hope to integrate myself well into the team, to get on well with everyone and the fans here in this beautiful stadium."

Dembele will have to wait until nearly two weeks to make his debut due to the upcoming international break before Barca host Espanyol in a Catalan derby on September 9.