Diego Costa has reassured Chelsea he will not play in Spain's

Diego Costa has reassured Chelsea he will not play in Spain's upcoming Euro 2016 qualifiers against Slovakia and Luxembourg if he is not fully fit. Although he has been in prolific goalscoring form since his summer move from Atletico Madrid, scoring nine goals in his first seven Premier League appearances, Costa has been struggling with a hamstring problem since last season and Chelsea boss Jose Mourinho revealed recently the 25-year-old was barely training. Mourinho would also have preferred to see his player rest during the international break in order to receive treatment.