Upset specialists Japan, who beat South Africa in 2015 when led by current England coach Eddie Jones, and stunned Ireland and Scotland en route to the 2019 quarter-finals, were hoping Jones takes them lightly.
"I hope that he thinks that we're far too behind England to be worried about at this stage," Japan coach Jamie Joseph said.
"He's got an intimate knowledge of pretty much everything in rugby apart from what we do. We're adapting all the time.
"Meanwhile South Africa face an uphill battle to become the World Cup's first four-time winners as they take on both Ireland and Scotland in Pool B.
"It's exciting, really, to know who your RWC pool opponents will be," Springboks skipper Siya Kolisi said.
Due to the coronavirus pandemic, seeding levels for the tournament draw were based on the world rankings on January 1, 2020, instead of after the autumn internationals as originally intended.
Organisers also moved the draw forward to be able to start selling tickets in March next year, before ticket sales for the 2024 Paris Olympics begin in 2022.
The dozen countries from the draw will be joined by eight qualifiers, with the final line-up to be known by November 2022.