Cape Town - Former Canada and South Africa centre Christian Stewart believes it will be tough for the Springboks to win the Rugby World Cup.

In an exclusive interview with Sport24, Stewart highlighted England and New Zealand as the two danger teams at the showpiece event in Japan.

"I don't know whether the Boks are good enough to beat England or New Zealand because the latter two teams can step up a notch," Stewart said.

Stewart, who played 14 Tests for Canada and three for South Africa in the 1990s, discussed an area in which he felt the Boks could come up short:

"With George Ford and Owen Farrell in the 10-12 axis, England can click it up to a different gear and their attacking intelligence is superior to South Africa's. South Africa doesn't have the 10-12 combination to really play.

"I'm a fan of Damian de Allende and Frans Steyn as rugby players, but I think that the way we have decided to play the game is that we want those guys to smash it up as opposed to structure play. If you look at Farrell's attributes he has not step and no pace, but he’s an unbelievable 12. That tells you something about what the 12 should be doing.

"Rassie doesn't want our 12s to be structuring play, he wants our 12s to be target runners and ball-carriers. It's why the Boks wouldn't go with a Handre Pollard-type player at 12. If the Boks go on to win the World Cup it will be fantastic, but if they don't I think we will look back at this World Cup and say, 'We didn’t quite get the 10-12 combination right.' I believe that is where we could lose it."

Stewart, who played his provincial rugby for Western Province, added that the big game of the World Cup would be a potential New Zealand-England semi-final.

"At this point, they would arguably be the two favourites. I just think the overall intelligence on attack of both England and New Zealand is superior. In terms of their attacking intelligence, they are ahead of the game at this time."

READ Christian Stewart’s full Q&A interview with Sport24