Cape Town - Suggestions that Siya Kolisi is captain of the Springboks to score political points are "insulting", says national coach Rassie Erasmus.

Kolisi became the first black man in history to captain the Springboks this year, and he went on to win 7 of the 13 matches in which he led the Boks in 2018. 

With some strong competition in the loose trio and the likes of Duane Vermeulen taking clear leadership positions on the field this year, there have been suggestions that Kolisi's appointment is more to do with politics than rugby. 

It is a view that Erasmus knows exists in some circles, but he blasted that suggestion in an exclusive interview with SuperSport's Matt Pearce. 

According to Erasmus, Kolisi will lead the Boks up to and in next year's World Cup in Japan as long as he is not injured. 

Erasmus praised the leadership style of the 27-year-old, saying that he had actively given other members of the squad more responsibility.

"When Siya was appointed my plan was not to do a show on what it meant politically. I was looking at what was best for the team … I didn't expect this massive boom around Siya being captain," Erasmus said in the interview.

"I don't think Siya expected it. He didn't just have the job of being the Springbok captain on the field … he had all these other things happening around him and if I knew that, I probably would have done it a little bit slower with him and phased him in as captain.

"There are a few people, and I really don't understand why, who have said that it is just a show for us and that he is not really the captain.

"It's almost challenging Siya's intelligence for me. Are people really saying that Siya is stupid enough to sit there and not really be the captain and we're doing this all for show?

"This is a guy who sits in my office every day, we discuss tactics every day, we tour together. It's almost like people who say things like that are challenging his integrity because we love him as our leader and the way he is doing it.

"The way he has brought in guys like Warren (Whiteley), Duane (Vermeulen), Jesse (Kriel), Handre (Pollard) and Elton (Jantjies).

"We (the coaches) don't even go to the referee meeting anymore. Siya takes three guys and goes to that meeting and those are the role players he uses in the match. Siya's role is to regulate the climate, the happiness, the team spirit, the intention."

Under Kolisi's leadership in 2018, the Boks won 7 of their 13 matches.

Pieter-Steph du Toit led the Boks in their defeat against Wales in Washington in June, giving the Springbok class of 2018 a final ledger of played 14, won 7, lost 7.