Japan had set their home tournament alight with a scintillating style of organised chaos that swept them through their pool unbeaten with victories against tier one nations Ireland and Scotland.
Their fairytale run, however, ended against a formidable Springboks defensive effort that slowed the Japanese speed, while the South Africans, who only led 5-3 at halftime, relied on halfback pairing Faf de Klerk and Handre Pollard to keep them pinned in their own half.
Relentless South Africa beat England to win Rugby World Cup
The Springboks, who scored three tries - two from winger Makazole Mapimpi - but wasted a string of other chances, will now face Wales in the semi-finals in Yokohama next week after they recorded a 20-19 victory over a 14-man France, who had lock Sebastian Vahaamahina sent off at Oita Stadium earlier on Sunday.
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