Tonga received a huge boost after a gutsy showing against South Africa at the Rugby World Cup on Sunday with coach Toutai Kefu insisting more time together and extra matches for the small island nation will further increase their competitiveness.

Tonga were feisty and physical but undone by their errors as they lost 49-18 to the defending champions in Marseille

“We dominated territory and possession; we just probably needed a little bit more in our attack,” said Kefu, the former Australia international.

“I thought we slowed the game down really well. I think there was a couple of moments when we had the ball, especially against their line, with the pick-and-go where we probably needed to vary our attack a little bit more.

"I thought it was probably too forward-dominated. We got some sleek backs that we didn’t use better.”

However, Tonga were the first side to score three tries against South Africa in 17 World Cup games since the Springbok’s shock defeat by Japan in Brighton in 2015.

“I didn't know that. That's nice. That's good. I'd rather have a better result, though,” Kefu added.

“Look, we were always just going to judge ourselves on our performance today and I thought the boys had a real dig.

"We said to the group before the game, 'put on a performance out there that when you come off the field, you're absolutely proud of your family and proud of your village, regardless of the score' and I think they did that."

Progress now for Tonga would come from playing more tests.

"We've got the talent now. The eligibility rules opened that door for us. Now we need time to really blend," said Kefu.

"A third of my squad plays in France, a third play in the U.K, the other third are in New Zealand and then a couple in Japan. It's going to take longer for us to get on the same page.

"If you look at today, there were three or four turnovers that led straight to tries for South Africa. Spending more time together and getting regular competition, we'll fix that."

Kefu expects Tonga to finish the tournament in France with a flourish when they meet Romania in Lille next Sunday in their final Pool B game.

“We're tracking in the right way, which means we'll have our best game next week. And then the tour's over! It happens every campaign. I think if we can play to our best, I think we can get a really good result.”