Tonga captain Nili Latu was left counting the cost of missed penalty goals as his charges went down 45-16 to Argentina in Leicester on Sunday.
At 20-16 down on 42 minutes, it looked like the Islanders were on the right track to create a similar shock win to that of 2011 against France.
However, the Pumas pulled away later in the second-half and ended the game with five tries as they put one foot into the World Cup last eight.
"We were in the game," flanker Latu told the press after the game.
"We started strong after the break but one thing that let us down today was composure with the ball as we turned it over a lot.
"Full credit to my boys though, we didn't want to just turn up today. It wasn't the result we wanted but look forward to the challenge of the All Blacks next week."
Latu firmly believed that Tonga had the game in their grasp early in the second-half and admitted the errors cost them, particularly kicks at goal.
"Momentum was on our side," he added.
"I've talked about the mistakes creeping in and Argentina scored because of it. We missed five kicks today and our team strives on confidence. But they are little mistakes that we can control and fix for the New Zealand match. I know we've got one more big game up our sleeve."