Barcelona boss Ernesto Valverde has conceded that Lionel Messi is unlikely to be available for the club's 2019-20 La Liga opener away to Athletic Bilbao on August 16.

Messi, who represented Argentina at the Copa America earlier this summer, is carrying a calf problem which has seen him miss Barca's preparations for the new campaign.

Valverde has admitted that the 32-year-old is still injured and therefore a huge doubt to take on Bilbao, where the Catalan giants will be looking to make a strong start to their title defence.

"I would love it if Messi was still on holiday, but he is injured. I would like to say he will be available to play against Athletic, but that is difficult to see," Valverde told reporters.

The Spanish champions have beaten Napoli on two occasions in their last two pre-season matches.

Ivan Rakitic scored the winner in a 2-1 success on Wednesday, before Luis Suarez, Antoine Griezmann and Ousmane Dembele also registered in a 4-0 victory on Saturday.