Barcelona suffered a shock 1-0 defeat to Athletic Bilbao at San Mames Stadium on Friday evening.

A stunning Aritz Aduriz scissor kick in the 89th minute sunk the Catalans, condemning them to their first opening day defeat since the 2008/09 La Liga season.

Ernesto Valverde knew there could only be one outcome when the ball was floated towards a striker whom he worked with for four years at the Basque club.

“When I saw him shaping to shoot I knew exactly what would happen, it’s an area of the game he utterly dominates and I wasn’t surprised by the strike at all,” the Barca manager told reporters, per BBC Sport.

“With Aduriz on the pitch any ball crossed into the area is deadly and he scored a brilliant goal.”

Barcelona were expected to kick off their bid for a third consecutive league title with a win, even without the injured Lionel Messi.

His absence was felt throughout the 90 minutes as the visitors registered just two shots on target despite dominating possession as per usual.

Luis Suarez was forced off with an injury late in the first half, leaving his replacement, Rafinha, Antoine Griezmann and Ousmane Dembele to lead the line.

Griezmann struggled in his first appearance since completing a £107 million switch from Atletico Madrid, though he could be forgiven for needing some to gel with his new teammates.

Dembele, on the other hand, has no such excuse in his third campaign at the Nou Camp.

If this is to be the season when the 22-year-old finally comes into his own, it certainly didn’t get off to a promising start.

Someone has compiled a 90-second video of every wayward pass, loose touch and failed dribble Dembele produced against Athletic - and it’s pretty difficult to watch.

Dembele’s attempt to prevent Ander Capa from swinging in the cross to set up Aduriz’s winner was particularly woeful, it must be said.

His ‘effort’ prompted a furious response from Gerard Pique, who clearly thought the Frenchman could’ve done more to close down the delivery.

While defending isn’t his forte, Dembele really can’t have any complaints.

The best attacking players in the world make sure they contribute to their side even when things aren’t clicking in the final third.

While it’s too early to say with any certainty, it looks as if Dembele still has a lot of growing up to do this season.