Players need to be involved with their national sides despite a crammed calendar causing concerns over the impact on players' health, Spain manager Luis de la Fuente said before their Nations League clash against Switzerland on Sunday.

The European champions will face Switzerland in Geneva after both teams dropped points in their competition openers, with the Swiss losing 2-0 to Denmark and Spain finishing goalless against Serbia.

"Tomorrow we'll have a very tough opponent in front of us. I think that during the European Championship we were the teams that played best," De la Fuente told a press conference on Saturday.

"Tomorrow we will see two teams of a very high level, perhaps in one of the most important games that could be currently played in Europe. We are planning to try to enhance our strengths and minimise those of our opponents."

The Spanish coach was questioned about increased fixture congestion and its consequences for the national team.

"We think of the players first. But they also have to play with the national team," De la Fuente said.

"The calendar is agreed (by others), we comply with it, nothing else. (But) it's our country, our national team, and I think we should give it the importance it has.

"All the players want to go to the national team and the clubs - without exception - want their players to be internationals. We are victims of this calendar, not the culprits."

The Spanish coach added that he would not agree to reduce the contributions of players at high profile teams to protect their performance at club level.

"Our duty is to represent our country, to put out the best players, to compete to win. We have a huge responsibility, a great prestige to defend and the only way I would know how to do it is to put the players I think are the best," he added.

"Besides, we have to be fair, and I would not be fair if I protected some more than others because of their club."

Sunday's fixture could see the return of midfielder Rodri, who is yet to play for his club Manchester City after he was forced off at halftime during Spain's win against England in the Euro 2024 final.

"We always prioritise the player's health. (But) Rodri is perfectly trained and at some point he will have to start playing, either here or with his club," De la Fuente said.

"If we understand that tomorrow he has to start, then he will start without any risk. But then, football is the way it is and anything can happen."