Peru kick-started their World Cup qualifying campaign with a hard-fought 1-0 win over Paraguay on Saturday (AEDT).

A first-half goal from Jefferson Farfan was all Ricardo Gareca's men needed at the Estadio Nacional de Lima.

The much-needed win helped Peru to its first win of the campaign, while it marked Paraguay's first defeat.

Farfan produced the decisive moment after some questionable defending by the visitor in the 20th minute.

The former Schalke forward was left in space on the left before receiving a pass from Paolo Guerrero and finishing past Antony Silva.

There were question marks over Silva, who was beaten at his near post by the powerful effort.

Paraguay rarely threatened and it came as no surprise for a team that had scored just once in its opening two qualifiers.

The win is a huge boost for Peru ahead of Wednesday's (AEDT) clash against Brazil, while Paraguay hosts Bolivia.