Viliami Moala beat two defenders and scored a long-range try on fulltime as Tonga upset medal prospect South Africa yesterday in the Commonwealth Games rugby sevens tournament.
The Tongans scored inside the last minute to level at 19-all and then Moala swooped on a South African turnover inside his own half and crossed for the winner.
The South Africans will now have their work cut out in a pool that also includes Samoa, easy 31-10 winners over Uganda.
Gold-medal favorite Fiji beat Canada 31-14 in the opening match and pounded Niue 63-0 to lead Group B, while the Canadians recovered to edge Scotland 10-7 in another upset.
Two-time defending champion New Zealand scored 21 unanswered points in the last four minutes to beat Wales 35-10 and followed up with a 41-7 win over Namibia in Group A. Wales rebounded with a 33-0 win against Kenya.
Australia and England -- finalists at the last 15-a-side World Cup -- opened the Group C matches with comfortable wins.
Wallaby fullback Chris Latham scored three tries in Australia's 73-0 drubbing of Sri Lanka. England beat Cook Islands 35-5.
All four of Australia's full internationals -- Latham, Lote Tuqiri, Matt Giteau and backrower Scott Fava crossed for first-half tries.
"Every game from here on in will be a lot tougher and we have to be careful we don't get a false reading from the scoreline," coach Glen Ella said.
Quarterfinals were to be decided after yesterday's evening matches.