Chelsea striker Diego Costa admits his national career with Spain is already frustrating him.
The Brazil-born attacker, 26, pledged allegiance to the Spaniards at the beginning of 2014 after making two appearances for his country of birth but has failed to fire for la Furia Roja.
Costa has netted just one goal in seven international appearances for the 2010 World Cup winners and will have to wait to add to that tally after failing to prove his fitness for Friday's Euro2016 qualifier against Ukraine because of the hamstring injury he sustained in the weekend's 3-2 Premier League win over Hull City.
"I was in good form, I thought everything was finally going to work out," Costa said in an interview with Spanish sports newspaper Marca.
"You always arrive (to the national team) with some aches. But this time, I would have arrived without any pain.
"I really wanted to prove my form and my worth...but again it (injury) happened."
Costa added: "My history with the national team is that it still hasn't really started. I haven't done anything yet.
"The national team is something I think of.
"I am sorry that I cannot bring what I would like to.
"Something always happens when I get close to playing for Spain.
"It bothers me from a personal standpoint but I hope this will end.
"I've gone through a lot to be in the national team and I hope good times will come."
