Captain Brian O’Driscoll scored the opening try before Keith Earls touched down twice in the second half as Ireland topped Pool C and set up a quarter-final match-up against Wales next weekend.
And Mallett is tipping Declan Kidney’s side for further success, admitting it is difficult to identify any weak spots in the Irish team.
“They’ve got a team who can knock over anyone in that side of the draw in the quarters and the semis. I don’t think any team can be confident against them,” Mallett said. “Where is their weakness?
“They were outstanding. We had to play really well to stay in touch but then their backs began to control the game incredibly well.”
Ireland flanker Sean O’Brien was named man of the match after a ruthless display against the Italians, but the Leinster star insists their is more to come from them in New Zealand.
“We feel good,” said O’Brien. “We’ve done our job and topped the group, but this squad of players isn’t happy with that.
“We want to do bigger and better things than this. There’s way more to come from this team.”
He added: “We said after the second pool game we’re halfway there and now we’ll say again, we’re only halfway there. There’s no point thinking we’ve achieved something now because we’ve done what we’ve done.
“Obviously it’s good, but we still want more and Wales is next on the list. Hopefully we can take it up a notch.”
Ireland face Wales at the Wellington Regional Stadium on Saturday morning with the winner to take on either England or France.
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