Spain forward Diego Costa has insisted that he will be fit for La Roja's World Cup opener against Netherlands on June 13.

The Atletico Madrid striker has been troubled by a hamstring injury over the last couple of months, which placed his spot in the Spain squad for this summer's competition in severe doubt.

The 25-year-old eventually made the travelling party, however, and has declared himself available for the Group B clash in less than two weeks.

"I think I'm fine. I tried the week after the Champions League but had almost no time to recover. Now I want to train because I've had a few weeks without doing anything. All that matters is to train a little," he told AS.

"Can I get to the first World Cup match? Sure, why not? After the Champions League final they wanted to do a test and I came out of it very well because there wasn't anything that could move me away from the World Cup.

"I always look forward to the end of the season but now, even more so."

Costa was born in Brazil but switched his allegiance to Spain after gaining citizenship towards the end of 2013.