Diego Costa has been warned over his place in the Spain squad (Picture: Getty)

Chelsea striker Diego Costa has been warned he has to be playing regular football if he is to have any hope of making Spain’s squad for next summer’s World Cup finals in Russia.

The 28-year-old is out of the first-team picture at Stamford Bridge at the moment after failing to get a summer transfer back to Atletico Madrid, who remain keen to land him in January.

Atletico were under a transfer ban this summer, which complicated the deal, though various reports suggest an agreement could now be close for Costa to move to the Spanish capital in the winter.

Until then, however, Costa continues to train away from Chelsea after falling out with manager Antonio Conte, and Spain boss Julen Lopetegui admits his situation is something of a concern.

Costa hasn’t played for Chelsea this season (Picture: Getty)

Discussing his prospects with the national side, Lopetegui made it clear he couldn’t currently consider him for selection due to his lack of recent involvement on the pitch.

‘Costa’s summer has been unusual, strange, complicated – not just for him but for his club,’ Lopetegui told beIN Sports. ‘He is still a Chelsea player. It’s a complicated issue.

Julen Lopetegui admits Costa needs to be playing (Picture: Getty)

‘Our hope is that he will resolve his situation as soon as possible and that he can compete, train and play, which is what he likes doing the most and what interests the national team.

‘It’s rather complicated that a guy who doesn’t train and doesn’t play can be with us, but that’s all it is.

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‘He wasn’t ready to play with us (against Italy and Liechtenstein), that was the reality and what we had to deal with. That is the reason why he wasn’t with us.

‘He needs to train and play in order to be considered.’

Costa has been at Chelsea since 2014 and has shone for the club, though he has been keen to return to Spain after failing to fully settle in London off the pitch.

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