This comes after the Sunwolves fell to the second heaviest defeat in Super Rugby history - a 92-17 pakslae by the Cheetahs in Bloemfontien.
The Australian quit as Brave Blossoms boss after last year’s World Cup in which his Japan team stunned South Africa, before spending two weeks as Stormers coach.
He told reporters in London: “The only reason I’m here now is because they stuffed up how to set [the side] up, because they didn’t put professional people in place, and that’s why they’ve got such a poor squad.
“They are terrible. The whole purpose of having a Super Rugby team in Japan is to help promote the national team. So you’ve got guys now that have been pulled out of [New Zealand] playing on the wing. It’s got no relevance to the Japan national team there.
“They’ve lost six games and everyone’s happy they’re fighting hard.”