The Bulgarian side took an early lead as Graham Carey found space in the box after a quick counter attack and rifled into the roof of the net. The Giallorossi were level midway through the half through a magnificent Lorenzo Pellegrini effort however, as the captain brought the ball down outside the box and flicked a curling effort into the top corner.
Roma were ahead shortly before halftime as Stephan El Shaarawy collected the ball from Eldor Shomurodov and fired in from the edge of the box. The lead was extended on the hour mark as Pellegrini found his second, rolling in a tame effort after meeting a Riccardo Calafiori cutback.
CSKA finished the match with 10 men after Yanic-Sonny Wildschut picked up a second yellow card for a cynical foul on Carles Perez, and Roma took full advantage as Gianluca Mancini tapped in from a freekick. Tammy Abraham broke the offside trap to add a fifth and complete the rout, as Jose Mourinho’s side made a dream start to their campaign.