But fears he might miss entire tournament prove unfounded...
Iniesta is not ruled out completely for Spain's first match, but doctors emphasised that the player's rate of recovery from the muscle injury in his right leg will determine his ability to play.
The Spanish federation revealed that an MRI scan revealed swelling but it "does not appear to be a tear." Iniesta left the hospital telling reporters "I'm okay" and in five days will be subjected to more tests to determine his progression.
"We cannot determine the recovery time," a Spanish statement read, "but the player's chances of playing the first game of the World Cup have not been discarded."
Iniesta was substituted in the 39th minute of last night's friendly match against Poland after noting discomfort in his right leg. Iniesta was having an exceptional match prior to the injury, playing a crucial part in Spain's first two goals.
Should the Barca midfielder be unable to take the pitch in Spain's first match in South Africa, possible alternatives along the wing will be Pedro (who came on for Iniesta in last night's match), Jesus Navas or Juan Mata.
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