Diego Costa first asked to quit Chelsea during their pre-season training camp in Los Angeles last year, leaving the club bemused over his claims to be upset at being told by text message from Antonio Conte in June that he could go.

The Brazilian-born Spain striker made three requests to leave Chelsea during the course of last season. After asking to join Atletico Madrid last summer, his intended destination in January was Tianjin Quanjian, of the Chinese Super League, before he reset his sights on Spain with a third request, which was granted towards the end of the campaign, leaving only the terms of his departure to be finalised this summer.

Costa has spent the summer in Brazil, where he gave an interview over the