Italy 36-12 Tonga
Italy huffed and puffed before finally putting paid to some impressive Tongan resistance at Canberra on Tuesday.
The Azzurri were made to work hard in a scrappy game and twice came within a whisker of losing the lead.
Tonga played well in patches and tries from John Payne and Tevita Tu'ifua were no more than they deserved.
Italy, in contrast, were well below par and, despite tries from Dallan brothers Manuel and Denis (2), will thank fly-half Rima Wakarua for an impressive night with the boot.
The naturalised New Zealander converted eight out of nine for a valuable 21-point haul on his international debut.
The first-half was a tale of Tongan power and Italian inefficiency.
The Pacific islanders started and finished the half the stronger, but their periods of improvement sandwiched three impressive kicks from Wakarua.
The match started disastrously for Tonga when Ipolito Fenukitau was yellow-carded for a blatant high tackle on Gonzalo Canale in only the second minute.
The former ACT favourite never managed to return and was replaced by Stanley Afeaki - who joined his brother Inoke - after the required 10 minutes.
By that time, Tonga were already six points down with Wakarua, who replaced Ramiro Pez in the Italian squad, looking every inch a Test number 10.
The same could not be said for his opponent Sateki Tu'ipulotu, who struggled with the boot and failed badly with two kickable penalties.
With half-time approaching Tonga struggled to play themselves back into the game.
But, as the Canberra rain began to fall, they finally picked up the pace and put together their best move of the half to allow Payne over wide on the left for the game's opening try.
It was no more than Tonga deserved and when Tu'ipulotu's kick sailed through the posts it brought the World Cup within two points of its first major upset.
Thankfully for the Italians, the Tongan barrage stalled in the second period.
Instead, it was the blue shirts who hit back first through Manuel Dallan.
Seconds later, Tonga suffered another blow when captain Inoke Afeaki was stretchered off unconscious after a clash of heads.
Dallan then turned from hero to villain when he followed up his try with a dismal tackle on Tu'ifua to allow the winger a straight-forward run in.
Tu'ipulotu's conversion drifted wide, before Manuel's brother Denis grabbed his late double to seal a tidy - if not entirely impressive - Pool D victory.
Italy: G Canale; N Mazzucato, C Stoica, M Dallan, D Dallan, R Wakarua, A Troncon (capt); A Lo Cicero, F Ongaro, L Castrogiovanni, S Dellape, M Bortolami, A de Rossi, A Persico, S Parisse.
Replacements: C Festuccia, S Perugini, C Checchinato, M Bergamasco, M Mazzantini, F Mazzariol, A Masi
Tonga: P Hola; S Fonua, G Leger, J Payne, T Tu'ifua; S Tu'ipolotu, S Martens; t Lea'aetoa, E Taukafa, H Lavaka; V Vaki, M Ngauamo; I Afeaki (capt), I Fenukitau, B Kivalu.
Replacements: V Ma'asi, K Pulu, U Latu, S Afeaki, T Alatini, J Ngauamo, S Va'enuku