South Africa recorded a routine bonus-point win over 14-man Italy in Shizuoka to keep their World Cup hopes alive.
Handre Pollard converted tries from Cheslin Kolbe and Mbongeni Mbonambi, and added a penalty to put the Springboks 17-3 up at the break.
After the Azzurri had prop Andrea Lovotti sent off for a tip-tackle, Kolbe crossed for his second score.
Lukhanyo Am, Makazole Mapimpi, RG Snyman and Malcolm Marx also went over as South Africa went top of Pool B.
The two-time winners know victory in their final pool match against Canada on Tuesday (11:15 BST) is likely to be enough to secure a quarter-final berth, with Italy facing holders New Zealand in their last game on Saturday, 12 October.
Having lost 23-13 to the All Blacks in their opening match of the tournament, South Africa coach Rassie Erasmus admitted the meeting with Italy was "do or die" for his side.
But the Boks, who were one of the pre-tournament favourites, had any nerves settled by Kolbe's early try when the winger beat two men to touch down in the right-hand corner.
The contest was expected to be a battle between the forwards but Italy lost both their tighthead props, Simone Ferrari and Marco Riccioni, to injury in the first half, leading to uncontested scrums for the final hour.
South Africa pushed home their advantage after Lovotti was sent off early in the second half for his part in an ugly tip-tackle on number eight Duane Vermeulen but will have concerns over the fitness of Kolbe, who picked up an ankle injury in the closing stages.
