New Zealand made it three wins from as many games at the Rugby World Cup, needing a big second half to thrash Namibia.
With just a four-day turnaround, the Springboks opted for changes for their Rugby World Cup clash against Canada.
Leaders Lyon are the only unbeaten side in the Top 14 after they won a top-of-the-table encounter against Bordeaux-Begles.
Ulster suffered a hammering in Bloemfontein, where wing Anthony Volmink scored three of nine tries for the Cheetahs.
With victory over Samoa, 2019 tournament hosts Japan have the chance to win the group at a Rugby World Cup for the first time.
Despite securing a quarter-final spot with a game to spare, Eddie Jones wants his players to prepare for a tough game against France.
Samoa were eliminated from the Rugby World Cup as Japan maintained their 100 per cent record and earned a late bonus point.
Adam Coleman and Lukhan Salakai-Loto were sent to the sin bin for high tackles but Michael Cheika did not want to talk about it.
England clinched a place in the knockout stages at the Rugby World Cup, aided by a red card for Argentina's Tomas Lavanini.
Tomas Lavanini was sent off for a high shot on Owen Farrell in the first half as England eased to victory over Pool C rivals Argentina.