"We know we have the three strikers, but that's not enough. It's enough to create chances; to score goals, you need midfielders coming into the box as well and he's doing it really well.

"He's giving the team really more quality if he's reaching the opponents' box and giving assists and scoring goals. That's what we need, what he needs, but that's the development of the player that's going really fast."

De Jong broke the deadlock at the Martinez Valero Stadium after 39 minutes when, in trying to prevent Antoine Griezmann reaching Martin Braithwaite's cross, defender Diego Gonzalez could only divert the ball into his path to hand him a tap-in.

Barca keeper Marc-Andre ter Stegen had to save from Emiliano Rigoni after the break as he looked to make the most of a defensive blunder, and it was not until the 89th-minute that Puig, who had only been on the pitch for two minutes, made sure of the win.

Koeman said: "I'm really happy, for sure, about the way we played today. In a difficult period with a lot of games, every three days, against a team which had the whole week off to prepare for today's game, we played really concentrated with good ball possession.

"It was difficult to score because defensive-wise, they had a lot of people behind. But we had patience and for sure, we pressed really well and they did not have any chances – maybe the second half, but it was out of a mistake by the Barcelona players."

The win took the Catalan club, who are now unbeaten in nine league games, above Sevilla into third place in the table, three points behind arch-rivals Real Madrid in second at the halfway stage.