Cape Town - England coach Eddie Jones is "100%" certain that the Springboks will be title-contenders at next year's World Cup in Japan.

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Jones was speaking in Cape Town after his side beat South Africa 25-10 in the third and final Test at Newlands on Saturday.

The result is Jones' first win in six Test matches, but it could not prevent his side from losing the series 2-1.

The Boks, after a disappointing two years under Allister Coetzee, slipped well off the radar when it came to possible title challengers in 2019.

Heavy losses to the All Blacks - home and away - contributed to that as did a shock loss to Italy in Florence on the 2016 end-of-year-tour.

The Boks under Coetzee were simply toothless when it came to taking on the best in the world, but since Rassie Erasmus took over as coach ahead of the 2018 international season there has been a renewed sense of optimism accompanying South African rugby.

Saturday's performance was poor, but it came after Erasmus had experimented with his team selection and given a number of fringe players - Elton Jantjies, Andre Esterhuizen, Chiliboy Ralepelle and Warrick Gelant - a start.

The result may not have gone South Africa's way, but there are promising signs.

And when asked if the Boks could win in Japan, Jones was convinced.

"100%," he said.

"I would have said so six months ago. You've got bloody good young players here and the side was always going to come together.

"It's incredible the depth of talent you've got here, and even though you have a lot of players overseas you have good, young players coming through."

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Jones also praised the work that Erasmus had done with the side.

"Rassie has done a good job of getting some wins for the side early," said Jones.

"The big difference between the Springboks now and the Springboks six months ago is that they work harder off the ball.

"They've got a strong maul, which is a big strength of South African rugby, and then when the opportunity comes they have the ability to spread the ball into space and they have guys on the outside who have the ability to make good decisions.

"They'll continue to get stronger."

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