Lamine Yamal and Nico Williams returned to full training with Spain at the team's base camp in Chattanooga, Tennessee, on Thursday.
Yamal, Williams and VÃctor Muñoz missed the friendly match against Peru on Monday because of injuries, and remained at the team's training base.
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Barcelona star Yamal has not played since April 22 because of an injured left hamstring.
Spain coach Luis de la Fuente said last week he expects Yamal to be "ready to play" in Spain's opening World Cup game, although he admitted that the Barcelona winger's involvement could be limited to "just a few minutes."
The European champions will take on Cape Verde in Atlanta on June 15 as they begin their quest for a second World Cup title.
Teammates celebrated Yamal and Williams' recuperation inviting them to run the gauntlet at the start of Thursday's training. Goalkeeper Unai Simón followed the two to celebrate his birthday.
After Cape Verde, Spain faces Saudi Arabia on June 21 in Atlanta and Uruguay on June 26 in Guadalajara, Mexico.
The Associated Press contributed to this report.
