The AC Milan player sustained a knock to his calf and has left the Italy training camp in Sistriere. He will now be unavailable for Italy's final preparation match against Switzerland. Pirlo is undoubtedly a key player for coach Macello Lippi due to his attacking creativity and he will be a big loss to the Azzurri's offence if he were to be ruled out of the World Cup. The extent of the damage to the 31-year-old is to be confirmed, but there are fears he could miss the tournament in South Africa altogether. The 31-year-old will go to Milan in order to have further tests done. Italy are drawn alongside Paraguay, New Zealand and Slovakia in Group F and will kick off their defence of the World Cup against Paraguay on 14 June.