Barcelona welcomed the likes of Frenkie de Jong and Antoine Griezmann to the club over the summer but didn't get off to the best of starts this season.

The defending Spanish champions lost 1-0 to Athletic Bilbao in their La Liga opener and have a mounting injury list - especially in attacking positions.

Lionel Messi was given an extended break after his Copa America excursions but the five-time Ballon d'Or winner has suffered a minor setback since returning to Barca training.

Other injuries to Ousmane Dembele and Luis Suarez meant Ernesto Valverde was searching for forwards to include in his squad to face Real Betis - and he opted for Anssumane Fati.

However, due to certain La Liga regulations, Barca needed official permission from the 16-year-old's parents in order to name him on the bench for the 5-2 win against Betis.

Who is Ansu Fati?

Ansu Fati is a young winger who usually plays for Barcelona B and he's been one of the most impressive prospects in the club's youth system in recent times.

Barca boss Valverde selected a front three of Rafinha, Griezmann and 21-year-old academy graduate Carles Perez at the Nou Camp on Sunday, with Fati as a substitute.

Why did Barca need permission to include Fati?

It turns out that football teams in Spain's top-flight aren't allowed to field underage players in late-night matches unless they are granted permission from the player's parents.

So, with Barca 5-2 Betis kicking off at 9pm local time, the Catalan giants and Fati actually required consent from the Guinea Bissau teenager's parents in order for him to be eligible

Fati took his place in the Nou Camp dugout alongside top-class talents like Samuel Umtiti, Arthur, Arturo Vidal and Ivan Rakitic.

One of La Masia's crown jewels replaced Perez in 78th-minute to a huge ovation from supporters inside the stadium and he enjoyed a couple of nice touches before the final whistle.