Diego Costa’s future is still not resolved (Picture: Getty)

Chelsea are reportedly growing concerned they may be unable to sell Diego Costa for their desired transfer fee this summer due to his partyish lifestyle and possible weight gain over the summer.

The Spain international has been strongly linked with both Atletico Madrid and AC Milan in recent months but is yet to finalise a move away from Stamford Bridge.

Atletico have reportedly been reluctant to meet Costa’s £35million asking price, and Chelsea fear from looking through the player’s Instagram that he is currently lowering his market value, according to The Times.

The Blues have already signed Alvaro Morata as his replacement up front, but have failed to actually go ahead with offloading Costa since Antonio Conte made it clear he was no longer in his plans.

https://www.instagram.com/p/BVpuqsmFDf1/?hl=en&taken-by=diego.costa

The Italian notably sent the 28-year-old a text message informing him he didn’t plan on keeping him at the end of last season, but it remains to be seen if clubs will take a gamble on him.

Costa shone for Chelsea last season, scoring 22 goals in all competitions to fire the club to the Premier League title and FA Cup final, though he has never fully settled in London.

Costa is no longer in Antonio Conte’s plans (Picture: Getty)

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A return to Spain is thought to have been the striker’s first priority this summer, but Atletico boss Diego Simeone recently hinted a deal was off for the time being.

Chelsea will hope Costa isn’t in too bad shape after his summer off, but are aware he has returned to pre-season in less than ideal condition in the past.

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