Mohamed Salah’s 62nd-minute strike proved the winner on Monday, after Edin Dzeko had given the Italians a 1-0 lead just shy of the half-hour mark.
Liverpool’s Sheyi Ojo had cancelled out the opener with his third goal in two pre-season games on the stroke of halftime at Busch Stadium, but it was ultimately in vain.
Jurgen Klopp named a strong lineup as he fielded a front three of Roberto Firmino, Daniel Sturridge and new signing Sadio Mane, with Georginio Wijnaldum and James Milner also featuring for the Premier League side.
Roma were similarly strong as Radja Nainggolan started, with Dzeko and Salah up front alongside Stephan El Shaarawy. Kevin Strootman also featured in midfield as he upped his pre-season preparations following a nightmare 12 months with injury.
The Serie A outfit looked the better side for the majority of the contest, with Nainggolan’s tireless work in midfield making life difficult for Liverpool.
And the Reds’ defenders had to be on their toes early as Dzeko found a way through, only for Nathaniel Clyne to intervene.
But the former Manchester City star would not be denied, and he opened the scoring after 29 minutes, as he controlled a chipped pass forward with his chest and fired a low strike past Alexander Manninger from the edge of the box.
Liverpool responded well and grabbed a deserved equaliser prior to halftime through Ojo, who stooped low to head home after Dejan Lovren did well to keep an over-hit corner alive at the far post.
Salah, though, would restore Roma`s lead in the second-half, as the Egypt international capitalised on a defensive error from Andre Wisdom to score following Alessandro Florenzi’s cross.
Liverpool attempted to rally and almost levelled proceedings through Danny Ings’ dangerous free-kick in the closing minutes, only for Roma goalkeeper Alisson to make a fine save.