Higashiosaka - Tonga coach Toutai Kefu said his side were capable of inflicting another Rugby World Cup defeat upon France despite making "typical Tier Two errors" in a 28-12 loss to Argentina on Saturday.
Defeat, which followed their opening 35-3 loss to England in a tough Pool C that has been dubbed the 'group of death', all but ended Tonga's hopes of reaching the knockout phase.
They next play France, in Kumamoto on October 6, with Kefu's men looking to emulate the Tonga team that stunned 'Les Bleus' 19-14 at the 2011 World Cup in New Zealand - a tournament where the French reached the final before losing to the All Blacks.
Asked if Tonga could beat France again, Kefu replied: "I think so.
"Today there were a lot of positives and it could have been a different story if things had gone our way," the former Australia back-row forward added.
"We need to address those errors to be competitive and if we fix that we are well on the way to winning the big games."
Tonga were 28-0 behind as early as the 26th minute against Argentina at the Hanazono Stadium, the Pumas scoring four tries, including a hat-trick from hooker Julian Montoya.
"The start was just errors - poor skill, a bit of mis-communication," said Kefu.
"Typical Tier Two errors. But we never gave up.
"We could have thrown the white flag up, but the boys dug in," he added after a match where Tonga fullback Telusa Veainu scored tries in the 30th and 65th minutes.
But it might have been a different story when, in first-half stoppage time, Tonga wing David Halaifonua was bundled into touch just before he grounded the ball over the try-line by what looked like an illegal shoulder charge from Pumas lock Tomas Lavanini.
But South African referee Jaco Peyper, after consulting English television match official Rowan Kitt, decided Lavanini had made a fair tackle and disallowed the try.
Dangerous tackles have been a major talking point at this World Cup, while there has long been a perception that Tier Two nations such as Tonga rarely have refereeing decisions go their way.
"I thought it was a try - I thought it was a shoulder charge," said Kefu.
"If we would have got that we would have come out with a lot more belief and confidence (in the second half). It was not to be."
He added:"I looked at the front view. He (Lavanini) did wrap his right arm and I think that's why they probably got called off.
"We play by the referee's decision.
"I thought there were a couple of fifty-fifties we didn't get. It was critical for us.
"I'm used to it after four years of Tier Two. You move on."
Tonga, unlike major rugby countries, do not compete in an annual top-class tournament such as Europe's Six Nations or the southern hemisphere's Four Nations.
Kefu insisted more major matches between World Cups was the way for countries such as Tonga to rid themselves of those "typical Tier Two errors".
"More time together, more games against Tier Ones, access to our better players," said Kefu, when asked how Tonga could improve.
"We've had 10 weeks together before this World Cup and we had about six games.
"Annually, Tier Ones spend a lot more time together and have more games than us.
"The first thing we need is more time together and to play more competitive games."