Eddie Jones: I hope South Africa vs. Samoa is a UFC fight

Eddie Jones has picked out Japan's clash with Samoa as key to their chances of advancing to the World Cup quarterfinals - and hopes the Pacific Islanders' tie with South Africa on Saturday is like a "UFC fight."

After shocking the Springboks in their tournament opener last weekend, Japan were brought back down to earth by Scotland on Wednesday as Vern Cotter's side rallied to a rampant 45-10 victory in Gloucester.

Samoa beat the USA in their opening game last Sunday which, along with Scotland's win at Kingsholm, has blown Pool B wide open. Japan face Samoa on October 3 and Jones hopes their next opponents endure a gruelling encounter with the Springboks.

"Samoa in 10 days is key," Jones said during his post-match media conference. "If we knock them off we will have a fantastic chance.

"Hopefully South Africa versus Samoa is like a UFC fight, and they rough each other up. What comes around goes around.

However, Jones will be sweating on the fitness of Japan number eight Amanaki Mafi. After scoring their only try against Scotland, Mafi was stretchered off four minutes into the second half.

"Mafi was a big loss, he was a big loss to us," Jones added. "That boy is a big talent; two years ago he was playing second division university rugby in Japan and he has only played about five top league games in Japan. He had been denting the Scotland line, but we had to get over losing him, and we didn't."