Cesare Prandelli's side drew 2-2 in Sofia but, despite Bulgaria's second goal "stinking of offside" according to sports daily La Gazzetta Dello Sport, few in Italy thought the performance deserved more than a point, least of all Prandelli himself.
"The performance in Sofia was insufficient, negative," said the Italy manager on Saturday.
"This shows that you can forget the things that you've learned. We played lots too many long balls.
"We need to go back to working on concepts we were putting into practice as recently as two months ago."
Early reports suggest De Rossi, who was a doubt for Friday's game after hurting his ankle in Roma's 3-1 win at Inter Milan last Sunday, could be out for up to three weeks.
Forward Pablo Osvaldo, who in the absence of Mario Balotelli and Antonio Cassano continued his good early-season form by scoring both of Italy's goals on Friday, is almost certain to start alongside his Roma team-mate Mattia Destro, with Bologna's Alessandro Diamanti playing in behind the pair.
"Osvaldo is one of my most in-form players, right now he can make the difference." said Prandelli.
The defeat shattered Maltese hopes of a morale-boosting result ahead of their clash with Italy. The island side's last win during a World Cup qualifying campaign came against Estonia in May 1993.
Defender Andrei Agius, who plays for US Latina in Italy's first division, is relishing the prospect of facing Italy.
"This has to be the biggest game of my career," the 26-year-old told Reuters.
"I'm looking forward to the game because I know that I will be playing against one of the best teams in the world. We have to be objective about our targets for the match and we all know what we're in for."
