It took just 61 seconds for Italy’s wing-backs to team up for the opener, as Federico Dimarco glided up the pitch and delivered a pinpoint pass that culminated in Andrea Cambiaso converting despite the best efforts of Maxim De Cuyper and Koen Casteels.
Belgium were able to get on the ball after going behind but continued to look frail when called upon defensively, and had to wait until the 20th minute for their first notable response, when Jérémy Doku’s attempt was deflected behind by Riccardo Calafiori.
Soon after that, Dimarco hit an even more eye-catching pass to find Cambiasso again and this time Casteels palmed the Juventus man’s effort wide, where Mateo Retegui was lurking to finish and double the hosts’ advantage.
Davide Frattesi then headed wide after being found by Dimarco in a sign that the hosts were refusing to let up at all.
Pellegrini took that too far, though, and the Roma captain was needlessly sent off 40 minutes into the contest at the Stadio Olimpico for his challenge on Arthur Theate.
Making matters even worse, a routine from the ensuing free-kick ended in De Cuyper emphatically curling his strike out of Gianluigi Donnarumma’s reach to halve the deficit at the break.
Despite momentum switching, Alessandro Bastoni’s superb pass created an opportunity for Frattesi, but his Inter Milan teammate couldn’t find the target.
The centre-back soon returned to the fundamentals by rushing out to block Orel Mangala’s shot before Giovanni Di Lorenzo diverted Doku’s attempt over the crossbar.
However, the hosts couldn’t deal with the ensuing corner as Leandro Trossard pounced to poke the ball from Wout Faes’ header past Donnarumma.
It was all Belgium as Loïs Openda flicked wide from De Cuyper’s shot while the hosts used every trick at their disposal to slow down proceedings.
The approach worked with Dodi Lukebakio missing the target from the Red Devils’ best opportunity in the final quarter-hour, as Italy earned a point to stay top of UNL Group A2 despite losing their perfect record.
Belgium will be pleased to avoid back-to-back defeats, although they have won just one of their last five matches across all competitions.
Flashscore Man of the Match: Leandro Trossard (Belgium)