Samoa made a dream start to their World Cup campaign with a thrilling victory over bitter rivals Tonga in a punishing encounter at CUA Stadium on Friday.
Having taken a slender lead into the break, the Samoans struck in the 53rd minute through Wigan centre George Carmont to set up a match-winning eight-point buffer.
A string of handling errors cost Jim Dymock's men any chance of the win as Samoa set up camp deep in Tongan territory for the bulk of the second half to secure the four-tries-to-two triumph.
The result leaves Samoa's destiny in their own hands with a win over Ireland at Parramatta Stadium on Wednesday enough to see them finish atop Pool 3, while Tonga face a nervous wait to discover their fate.
The honours may have been shared in the battle of the war dances but it was Samoa who drew first blood in the third minute when winger Francis Meli crossed out wide.
Heavy defence forced the first mistake of the match as Tonga playmaker Feleti Mateo lost control of the ball deep in his own territory.
Samoan pivot Ben Roberts spotted space out wide to hand Meli the easiest of passages to the line for a perfect start and a 4-0 lead.
Tonga immediately launched an attack of their own, earning repeat sets deep in enemy territory.
The men in red looked destined to score through sheer weight of possession before Tevita Leo-Latu's pass found the waiting arms of Vagana who accepted the intercept and sprinted 90 metres to dot down adjacent to the posts.
Roberts added the extras and it was 10-0 to Samoa after 12 minutes.
The contest quickly developed into an arm wrestle punctuated by a series of bone-jarring hits from both defences before Manly-bound giant Tony Williams sent Michael Jennings over for Tonga's first four-pointer.
Williams attracted two defenders and then delivered a sublime one-armed flick for Jennings who juggled the ball before stepping his way to the line for the converted try.
Samoa looked certain to restore order when Vagana cut through some brittle goal-line defence, but the skipper inexplicably failed to ground the ball as the tryline beckoned.
Tonga made the most of the let-off when Leo-Latu thundered over on the half-hour - Williams' sideline conversion handing the men in red their first lead of the match at 12-10.
The match threatened to boil over from the restart when Leeds prop Kylie Leulua'i caught Fetuli Talanoa high but sanity prevailed. Referee Shayne Hayne nevertheless placed the big Samoan on report.
Samoa had the final say in the shadows of half-time when Canterbury Bulldogs winger Matt Utai crashed over out wide to send his side into the sheds with a slender two-point lead.
It was a frenetic start to the second half as both sides showed a willingness to attack but again Samoa were first to strike with a superb 60-metre effort.
Bradford back-rower Dave Solomona cut through the Tongan defence in midfield before linking with second-row partner Lagi Setu who in turn found Carmont for the converted try and a 20-12 lead.
A mistake from the ensuing kick-off put Tonga on the back foot once again but John Ackland's men could not land the killer blow as both Carmont and Smith Samau were denied by the officials.
Having weathered wave upon wave of attack, Tonga mustered a late raid of their own but could not manage a late consolation try in front of the vocal crowd of 11,787.
