Hosts Japan’s winning run at the rugby World Cup came to an end when they slid to a 26-3 defeat to South African in the quarter-finals on Sunday.
The Springboks will now play Wales, who earlier edged France 20-19 in a thriller in Oita.
Japan had won all their four pool matches, including victories over Ireland and Scotland, but South Africa got the upper hand in Tokyo after a tight first half in which the hosts trailed 5-3.
Winger Makazole Mapimpi went over for a try after four minutes and two more within four minutes from Faf de Klerk and Mapimpi in the second half put the Sprinboks in control.