Blues boss Sven-Goran Eriksson made 8 changes to the side that started Saturday's first defeat of the season at Arsenal, with Academy product Shaleum Logan and summer signing Gelson Fernandes coming in for their City debuts.
Rolando Bianchi returned to the starting line-up to partner Emile Mpenza in attack and the pair linked up superbly throughout. City had never won at Ashton Gate but Mpenza gave the Blues a 17th-minute lead before Bianchi struck an 81st-minute winner.
Two lengthy spells of City possession both resulted in Bianchi releasing Mpenza with a deft lay-off, and although Mpenza screwed his first chance wide, the Belgian striker fired his second effort above the home goalkeeper and into the roof of the net.
Mpenza returned the favour soon after, but Bianchi hesitated and the Italian's shot was deflected over.
Bianchi missed another good chance just after half-time when he fired inches wide from 10 yards, and then the hosts started to come into it.
England U21 goalkeeper Joe Hart, making just his 2nd appearance for City, came out to punch a cross clear but it went straight to Robins winger Michael McIndoe, who scored as Doncaster knocked City out at the same stage 2 years ago. McIndoe's volley looked destined for the top corner until Hart pulled off a fine save to tip the ball over.
However, the newly-promoted Championship side pulled level in the 69th minute as defender Bradley Orr turned the ball home after the Blues defence failed to deal with McIndoe's free-kick into the box.
The Blues were soon back on top, though, and Bianchi's strike ensured extra-time would not be needed. The home defence gave Bianchi space to collect Michael Ball's pass and the £8.8m summer signing set himself before drilling a 25-yard right-footed drive into the bottom corner to register his 2nd goal of the season and send City into the next round.
City: Joe Hart; Shaleum Logan, Vedran Corluka, Nedum Onuoha, Michael Ball; Stephen Ireland, Sun Jihai, Gelson Fernandes, Geovanni (Ousmane Dabo 83); Emile Mpenza, Rolando Bianchi (Paul Dickov 89).
Rolando Bianchi returned to the starting line-up to partner Emile Mpenza in attack and the pair linked up superbly throughout. City had never won at Ashton Gate but Mpenza gave the Blues a 17th-minute lead before Bianchi struck an 81st-minute winner.
Two lengthy spells of City possession both resulted in Bianchi releasing Mpenza with a deft lay-off, and although Mpenza screwed his first chance wide, the Belgian striker fired his second effort above the home goalkeeper and into the roof of the net.
Mpenza returned the favour soon after, but Bianchi hesitated and the Italian's shot was deflected over.
Bianchi missed another good chance just after half-time when he fired inches wide from 10 yards, and then the hosts started to come into it.
England U21 goalkeeper Joe Hart, making just his 2nd appearance for City, came out to punch a cross clear but it went straight to Robins winger Michael McIndoe, who scored as Doncaster knocked City out at the same stage 2 years ago. McIndoe's volley looked destined for the top corner until Hart pulled off a fine save to tip the ball over.
However, the newly-promoted Championship side pulled level in the 69th minute as defender Bradley Orr turned the ball home after the Blues defence failed to deal with McIndoe's free-kick into the box.
The Blues were soon back on top, though, and Bianchi's strike ensured extra-time would not be needed. The home defence gave Bianchi space to collect Michael Ball's pass and the £8.8m summer signing set himself before drilling a 25-yard right-footed drive into the bottom corner to register his 2nd goal of the season and send City into the next round.
City: Joe Hart; Shaleum Logan, Vedran Corluka, Nedum Onuoha, Michael Ball; Stephen Ireland, Sun Jihai, Gelson Fernandes, Geovanni (Ousmane Dabo 83); Emile Mpenza, Rolando Bianchi (Paul Dickov 89).