Hooker Julian Montoya scored a hat-trick in the first 26 minutes, as Argentina got their Rugby World Cup campaign back on track with a 28-12 victory over Tonga on Saturday that snapped a 10-match losing streak.
The Pumas failed to turn up in the first half of their opening loss to France last week, but there was to be no repeat at the Hanazono Rugby Stadium, with a fourth converted try from winger Santiago Carreras quickly wrapping up the bonus point.
But failing to add to their score in the second half would be of some concern, as the twice World Cup semi-finalists head into their clash with pool leaders England in Tokyo next weekend.
Tonga, who lost their first match to England, got their first two tries of the tournament through fullback Telusa Veainu either side of halftime and put in a great defensive effort to keep the Pumas out in the second half.
Argentina: 28 (Julian Montoya 3, Santiago Carreras tries; Benjamin Urdapilleta 3 conversions) Tonga 12 (Telusa Veainu 2 tries; Sonatane Takulua conversion)
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