Italy midfielder Andrea Pirlo was sidelined for the opening match against Paraguay in the World Cup because of a calf strain, a team source said on Friday.

The team source said Pirlo injured his left calf and left for Milan to be engaged in a recovery program.

The source said the AC Milan player was expected to leave for South Africa with his teammates on June 8.

Italy face Paraguay on Juen 14 in Cape Town before they meet the other Group F rivals Slovakia and New Zealand.

Under FIFA rules a team can replace an injured player up to the day before the opening game, therefore June 13 in Italy's case.