Javi Martinez has been forced out of the Spain squad for their upcoming friendlies against England and Costa Rica.
His club, Athletic Bilbao, have confirmed the defensive midfielder has returned from the international camp to undergo tests on an adductor muscle problem.
The 23-year-old has so far won seven caps but has been denied a regular place by Barcelona's Sergio Busquets.
Spain are set to face England at Wembley on Saturday before the world and European champions travel to play Costa Rica in San Jose on Tuesday.
Coach Vicente del Bosque has picked a strong squad while his England counterpart Fabio Capello is missing key players including striker Wayne Rooney and midfielder Steven Gerrard.
Jesus Navas has been recalled for the two friendlies. The Sevilla winger featured in last year's World Cup final but has not played for Spain since March and he is determined to seize the opportunity.
"I am going to fight to be in the final squad for Euro 2012," the 25-year-old told reporters at the RFEF's Las Rozas training facility outside Madrid.
"Being able to play in a tournament like that is something very important and you have to work hard to be there.
"Now I have been given the chance to come back into the squad and I am determined to make the most of it."