Chile manager Jorge Sampaoli has revealed that midfielder Arturo Vidal may not be fit to face Spain tomorrow afternoon.

The 27-year-old underwent knee surgery ahead of the World Cup and only managed an hour of playing time against Australia in La Roja's opening group game.

"I always said it was very difficult for him to join us here because he had a very serious injury and he had surgery," Sampaoli is quoted as saying by FIFA.com. "However, he managed to play some minutes against Australia and we'll see how he feels now.

"He's been training at a higher pace this week and we'll see if he can play some minutes tomorrow. We analyse his situation every single day.

"We know he's recovering now, he feels much better and he's here because he's really dedicated and willing to play. Arturo wants to play for the national team and we're very happy to have him here, if that doesn't damage him."

Chile follow up tomorrow's game with a clash against the Netherlands.