Griezmann's first goal was a swift response to Villareal's opening strike from Samuel Chukwueze, with the host's lead cancelled out within just two minutes before Barca's second strike followed seven minutes later.

"It is always important if you are down on the scoreboard to react quickly," Koeman said in a post-match press conference reported by Marca.com.

"It was in one minute and with a fantastic goal, it has given us confidence and it has been very important.

"It's a big step towards the title, every victory is a step forward, every match is difficult.

"We reacted well to their goal, creating chances, we were tired in the final stretch but we defended well.

"Sometimes you have to suffer, you can have a good opponent, someone who makes it difficult for you.

"We weren't nervous after their goal, in the end it was enough to get a win out of a complicated ground."