Spain midfielder Andres Iniesta suffered a "minor" thigh injury in the 6-0 win over Poland on Tuesday, according to the national side's doctor.
The 26-year-old was taken off in the 39th minute of the match, but those inside the Spanish camp were quick to stress that the complaint was nothing major.
"As he wasn't comfortable, we made the change—it's a minor muscle injury," said Dr. Oscar Celada.
He added: "We will calmly carry out tests, but we can initially rule out any muscle tear. It's a minor injury, but we have to take precautions."
Manager Vincente del Bosque also said the move was purely precautionary.
Iniesta will be examined today (Wednesday).
The Barcelona man was in sparkling form before coming off, setting up goals for David Villa and David Silva.
Xabi Alonso, Cesc Fabregas, Fernando Torres, and Pedro also got on the scoresheet as the European champions chalked up their 11th straight win.
They kick off their World Cup campaign against Switzerland on Wednesday June 16th.