Costa is on the lookout for a new team after being told by manager Antonio Conte that he is not in his plans at Chelsea, despite scoring 20 goals to help fire the Blues to the Premier League title last season.
Ladbrokes make it just 1/3 he joins the Blues this summer to replace the outgoing Diego Costa.
Chelsea refused to sell Costa to Chinese Super League interests in January, a fee that was rumored to reach as high as $100 million.
Alvaro Morata is Conte's next preferred choice to replace Costa if Lukaku can not be prevented from joining United, and there is mutual respect between the two men that stretches back to the summer of 2014, when Conte pushed for Juventus to sign him from Real Madrid.
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She said: "Personally, I can't speak for anybody else, but if my leg was broken I'd be crawling to the next ball". Heather Watson won 6-0 6-4 against Anastasija Sevastova at Wimbledon on 5 July 2017.
He may have been given the cold shoulder by his manager, but Diego Costa is most certainly a wanted man after 2.1million followers responded to a post from the Chelsea striker on Instagram - nearly entirely calling for him to join Besiktas.
Atletico's current bid falls way short of that, but the report notes that Chelsea will not be bullied into a cut-price for their talismanic forward as the money raised will undoubtedly fund a big-money move for a replacement.
Torino hitman Andrea Belotti also remains another option. It's added in the report that it will take a bid of around £90m to prise the Italian global away from Turin this summer, and that will surely be far too much for a player that has only really proven his quality at a high level over one season.