Duane Vermeulen thinks the Boks' best rugby is still ahead of them

The Boks have played some great rugby at this year's tournament so far - even in a losing effort against Ireland - but Vermeulen thinks they've still got a lot left in the tank.

"I'd like to say no (we haven't played some of our best rugby until now)," said the veteran forward, who will pack down at flanker this weekend in a loose trio with skipper Siya Kolisi and No 8 Jasper Wiese.

"If you look at our match against Ireland, it was one of the best pool games. But I certainly think we have a lot left in the tank.

"There are still a few things we have to work on, and we have to get that right this weekend and going forward because there are no second chances."

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Vermeulen also praised Siya Kolisi for his contribution to the Springbok team ahead of his remarkable achievement of leading South Africa for the 50th time, and said he was a key player both on and off the field.

"I've known him for a long time and when this chance came along, he grabbed it with both hands," said Vermeulen. "It's a fantastic achievement and hopefully there'll be a lot more to come from him."

Meanwhile, Springbok assistant coach Mzwandile Stick brushed aside all talk of a possible Rugby World Cup quarter-final spot and said their sole focus was defeating Tonga on Sunday and trying to earn a bonus point in the process.

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If the Springboks win the match with a bonus point, they will be in a good position to advance to the quarter-final stages regardless of the other results in the remaining Pool B matches, and Stick stressed that was their main objective in their crucial encounter against Tonga at Stade de Marseille.

"The mood in the camp is one of a Test week," said Stick.

"This could be our last eve of match media conference if we don't win, so we've been working hard at training and the eight-day turnaround (from the match against Ireland) gave us time to delve deeply into Tonga.

"We may not have gotten the result against Ireland, but the manner in which we played allowed the game to live up to its billing as one of the toughest in the pool stages. So, we are up and ready for this match."

The match against Tonga kicks off Sunday at 21h00.

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