A hard-fought victory over Scotland on Saturday has left Eddie Jones’s men one of just two sides, along with France, in contention to sweep the board in this year’s championship.
England, chasing a first Six Nations title for five years, have never lost to Italy, who were narrowly beaten in Paris last week, yet Gustard knows from bitter experience not to underestimate the Azzurri.
“Unfortunately I was involved in an England A team that lost, the very first England team at any level to lose to Italy. So it does happen,” said the former Saracens coach.
“If you focus on too many other things or you look too far ahead or you look towards Ireland or Wales and so on and start dreaming of other things, you’ll trip up fast. They’ve got a lot of good players, playing in competitive leagues as well, and they ran a good French team close at the weekend.”
Uncapped back-row forwards Maro Itoje, of Saracens, and Josh Beaumont, of Sale, are among a 25-man party Jones will whittle down when naming his team on Friday morning.
Harlequins flanker Jack Clifford, who came off the bench at Murrayfield, is also in contention, with Jones hinting he could pick a faster pack for the trip to Rome.