A Juan Mata goal proved sufficient for Manchester United to defeat former EFL Cup champions Manchester City by 1-0 and help the Red Devils advance into the quarter finals.
After a dreary first half in which neither of the bitter rivals managed a shot on target, the game came alive with Paul Pogba hitting a post moments before Mata found his mark.
Nine minutes after the break, the Spaniard scored as Zlatan Ibrahimovic holds off Nicolas Otamendi, and then squares for Mata to sidefoot home from eight yards out.
City boss Pep Guardiola had made nine changes to his side, who are now six games without a win in all competitions – his worst run as a manager.
However, the former Bayern Munich coach appears to have little interest or intent for a victory in the domestic cup competition, leaving vital offensive playmakers such as David Silva, Kevin De Bruyne and star striker Sergio Aguero on the bench.
Their best chance arrived early on when Kelechi Iheanacho headed over from six yards, while second-half substitutes Raheem Sterling and Sergio Aguero made little impact.
Victory was also United’s second in five matches, and only Jose Mourinho’s fourth win in 18 meetings with Guardiola.
His team will now face West Ham in the quarter-finals, while Hull City hosts Newcastle, Liverpool face Leeds and Southampton plays Arsenal from November 29-30.