Costa will not risk fitness.
Diego Costa will only line out for Spain in their Euro 2016 qualifiers against Slovakia and Luxembourg if he is fully fit.
Costa has been in sensational form for Chelsea this season, scoring nine goals in his first seven Premier League appearances, but a niggling hamstring injury has restricted his involvement in training.
Chelsea manager Jose Mourinho had hoped the 25-year-old would use the international break to rest, but he was called up to the Spain squad for the qualifying double-header and reported for duty on Monday.
Having been included in Vicente del Bosque’s squad, Costa is ready to play but he has warned he will only do so if he feels up to it.
“I’m here ready to play. I’ve had some problems but it’s getting better,” Costa declared,
“I’ve already played three games in a week and the coach [Del Bosque] knows that I carry some problems but I will treat them during the week.
“I don’t want to be in the middle [of Spain and Chelsea]. Mourinho has not told me anything. One has to take into account that many times I am the one that makes the decision depending on how I feel.
“Here I have the confidence of the coach, the technical team, and if there is a problem I tell them. If I’m here and I’m injured then I don’t play because it would be worse.”