Alcacer: Goals To Come For Costa   (Sky Sports)

Spain striker Paco Alcacer is confident Diego Costa will break his goalscoring duck for the national side sooner rather than later as La Roja prepare to face Luxembourg in a 2016 European Championship qualifying match on Sunday.

Costa, who joined Chelsea from Atletico Madrid in July, has regularly hit the target for the Blues but is still to find the back of the net for Spain.

Valencia frontman Alcacer, 21, believes Costa will open his Spain account soon and that he should follow the example set by captain Iker Casillas.

"He will score soon. I have a very high opinion of him," Alcacer told Marca.

"These good and bad patches are quite normal and soon his first goal will come.

"He (Casillas) is an example to follow. You can't judge him just by a single game."

Spain lost their second Group C match against Slovakia 2-1 on Thursday in a game where they created several chances but lacked the clinical edge to put them away.

Alcacer added: "On the one hand I'm very happy. Every time I go out on the field I try to do my bit, but on the other I wasn't happy as we lost the three points.

"After the game we weren't happy. We created some good chances but didn't convert them. Now we have to look to Sunday and the Luxembourg game, which is the first one to put all this behind us.

"The important game is not the last one, but the next one. This result is a blow, but the game against Luxembourg will serve to catapult us back up.''

Spain defender Cesar Azpilicueta called for Vicente Del Bosque's side to pull together after the defeat.

"None of us like losing. It's clear that we're all in the same boat. We have to take a long, hard look at ourselves, improve and be self-critical," the 25-year-old, who was an unused substitute against Slovakia, said.

"The criticism from the outside is understandable. We're going through a rough patch right now, but we're convinced we'll bounce back.

"Teams are making it harder for us and we have to deal with that. Spain hadn't lost a qualifier since 2006. We were young then and we never wanted this moment to come."

Luxembourg approach the match on the back of a dramatic 3-2 late defeat by Macedonia but coach Luc Holtz is focusing on the positives ahead of the clash with Spain.

"Late in the game, it could have gone in one direction or the other, it was a solo effort that made the difference," he told L'essential.

"But for us to score two goals, it is very positive.

"We must not dwell on this defeat and by Friday we'll focus on Sunday's game against Spain."