Italy tackle the All Whites in their second Group F game and the reigning world champions will be expected to win, despite the troubles they had in beating the Kiwis 4-3 in a pre-FIFA Confederations Cup friendly last year.
The combative AS Roma midfielder said that to understand what a defeat would mean for Italy one needs only imagine a reverse scenario in rugby.
"Losing to New Zealand would probably mean risking elimination, as has happened with France," said De Rossi who scored Italy's second-half equaliser against Paraguay in Cape Town. "We'd have a drastic position in the standings. It would be as serious as if New Zealand failed to get out the group stages at the rugby World Cup."
Although De Rossi is known for getting stuck in, he said he doesn't want Sunday's game to become a purely physical battle.
"I like the manly game but I also like playing the ball around. I don't like it when the game gets too physical, not because I'm afraid but because I like the beautiful game.
"But I haven't seen any really physical battles in the World Cup, they've all been good games and I think this one will be similar to the Paraguay game."
However the match goes, this is one that De Rossi admits Italy simply cannot afford not to win. There are teams that we should beat, we're better. We need to play our game and of course be careful," he said.
"They have big players so we won't be playing the ball in the air. But we're Italy and we should win.
"Not getting out of the group would be an absolute failure, it would also be a failure to not get past the second round.
"But when you get to the quarter-finals there are teams such as Brazil, Argentina, Spain and England, that's when little things can make the difference."