That would set up a winner-takes-all clash against Ireland this weekend with Declan Kidney’s men having the luxury of an extra three days’ rest.

But Mallett maintains his side cannot afford to underestimate the USA, who rested a lot of their team for the heavy defeat to Australia.

He said: “Obviously, I'd like to rest some of my key players at the end, to allow them to only play 60 out of 80 minutes, but if the game is really tight, which it could quite easily be against the United States, I think that it's difficult to do that because we must win at all costs.

“They rested their best players against Australia to be ready for this match," says Mallett. “They want to win their second match at a World Cup, because it is something they have never done before."

Mallett makes nine changes from the side that beat Russia 53-17 with captain Sergio Parisse, Tommaso Benvenuti, Mauro Bergamasco, Salvatore Perugini and Quintin Geldenhuys keeping their places.

Centres Gonzalo Canale and Gonzalo Garcia are reunited while Luke McLean takes over at full-back from Andrea Masi who has a thigh strain.

And Mallett has demanded a far higher standard in defence after shipping three tries against Russia.

He said: “I had a look at the players against Russia and there were a lot of defensive errors.

“It was the same backline that played Japan and to concede three tries against Japan and Russia isn't good enough.

“If this backline had played against Russia, we would have scored just as many points, but conceded far fewer.”

Italy team:
15. Luke McLean – Treviso
14. Tommaso Benvenuti – Treviso
13. Gonzalo Canale – Clermont Auvergne
12. Gonzalo Garcia – Treviso
11. Mirco Bergamasco – Racing Metro
10. Luciano Orquera – Aironi
9. Fabio Semenzato – Treviso
1. Salvatore Perugini – Aironi
2. Leonardo Ghiraldini – Treviso
3. Martin Castrogiovanni – Leicester
4. Quintin Geldenhuys – Aironi
5. Cornelius van Zyl – Treviso
6. Alessandro Zanni – Treviso
7. Mauro Bergamasco – Stade Français
8. Sergio Parisse – Stade Français

Replacements:
16. Fabio Ongaro – Aironi
17. Andrea Lo Cicero – Racing Metro
18. Marco Bortolami – Aironi
19. Paul Derbyshire – Treviso
20. Edoardo Gori – Treviso
21. Riccardo Bocchino – Aironi
22. Giulio Toniolatti – Aironi