Forwards Lamine Yamal and Nico Williams should be fit for Spain's World Cup opener, coach Luis de la Fuente said on Wednesday.
Yamal and Williams both missed the end of the club season due to hamstring injuries, but De la Fuente included them in his World Cup squad anyway, telling reporters last month he expected both to be fit for the global showpiece.
European champions Spain begin their Group H campaign on June 15 against Cape Verde in Atlanta.
"We are perfectly coordinated with the clubs, we are giving them continuation in a programme that was established some time ago and the truth is that the players are improving every day," De la Fuente said ahead of Thursday's friendly against Iraq.
He said the injured players were "progressing as expected" but that they would not be involved against Iraq in A Coruna.
Asked specifically about teenage star Yamal, De la Fuente added: "If everything continues as it has been so far, he could be ready on June 15, but that doesn't guarantee that he will play."
Spain will be one of the favourites at the World Cup in Canada, Mexico and the United States.
But De la Fuente insisted the tournament would be "historic because it is the World Cup in which the most teams have a realistic prospect of winning".
After facing Cape Verde, Spain will play Saudi Arabia on June 21 in Atlanta before finishing their group stage campaign against Uruguay in Guadalajara on June 27.