Pesamino scored three ties for Manu Samoa
Manu Samoa have qualified for the 2011 Rugby World Cup in New Zealand after beating Papua New Guinea 73-12 in Port Moresby on Saturday.
They are the second nation to qualify for the tournament after Canada booked their place earlier this month.
Manu Samoa will play in Pool D against champions South Africa, Wales and Fiji.
The last remaining place in the group will be taken by the winner of Africa's qualifying final between Tunisia and Namibia in November.
Samoa won 188-19 on aggregate over two matches against Papua New Guinea, having won 115-7 at Apia Park a week ago.
Wing Mikaele Pesamino opened the scoring with the first of his three tries after only four minutes at the Lloyd Robson stadium on Saturday.
Five more unanswered first-half tries by Eliota Fuimaono-Sapolu, Andrew Williams (2), Semo Sititi and a second for Pesamino, allied with four Titi Esau conversions, saw the visitors take a 38-0 half-time lead.
Roland Namo claimed one back for the Pupuks in the second-half before further scores from Fuimaono-Sapolu, Afa Aiono, Meki Magele, Pesamino and Gavin Williams.
Jack Maraha scored a late consolation try for the home side.
Meanwhile, Samoa has split from the Pacific Islands Rugby Alliance, which is likely to bring an end to the Pacific Islanders team which plays Tests against top rugby nations.
The Samoan Rugby Union this week informed fellow Alliance members Fiji and Tonga of its intention to withdraw.
It said the merged Pacific Island team had failed to produce financial benefits sought by member unions.