Costa has been linked with a move to China but insists that, if Chelsea wanted to sell him, he would only go back to Atletico and is not interested in any other clubs.
He stayed in England, but it hasn't quashed speculation he is set to leave, and Simeone's assistant Juan Vizcaino made his and the club's feelings on the subject known.
"I have no intention of leaving, I'm very happy here, I have two years on my contract, but if the club wants to sell me, there is one club I would go to".
Chelsea dominated the entire Premier League season, ending with the title with a seven point difference to second placed Tottenham.
The Brazil-born Costa said in August that he came close to returning to Atletico last summer but the La Liga club were unable to strike a deal with Chelsea.
'I will only leave Chelsea for Atletico, ' said Costa, who has two more years on his Chelsea contract. I know it's not easy with the Spain squad but I'm still young so I either stay here or go back to Atletico'.
"Everyone knows what my preferred club is, there's nothing to hide". Otherwise I'll stay with my current contract. I know that I have a chance to be called if I'm playing well and at a high level, and that's something I want.
"He is a boy who will take great steps". West Ham are reported to be preparing a cash-plus-player offer worth around £25m for 22-year-old Sunderland goalkeeper Jordan Pickford. "Every time people see me having dinner with someone they think it has to do with football".
Ultimately though, Chelsea may already have all the talent they need in wide areas.