A distinct lack of nerves from the Black Cats from the opening minute, combined with an attacking mindset in the early stages, rattled City. Adam Johnson almost managed to play in Emanuele Giaccherini after the 10 minute mark with a ball steered past the static Martin Demichelis, and Steven Fletcher was unlucky minutes later in guiding a header past the post from a Seb Larsson cross.
Larsson was lucky to stay on the pitch after a horrible studs-up lunge on Alvaro Negredo was missed by the referee, but Sunderland kept their focus to take the lead after 21 minutes. The goal came from an unlikely source, Phil Bardsley, back in from the wilderness under Gus Poyet, running into the box from the left wing before curling the ball expertly past Costel Pantilimon.
As expected, City notched up the pressure on the Sunderland goal, but their chances were, for the most part, kept to shots from range and snatched efforts from just inside the box. Sergio Aguero flicked a header wide of the post from an Aleksandar Kolarov cross in what was City's best first half chance.
The second half saw Sunderland keep their shape and defensive composure in the face of sustained City pressure. The visitors introduced much-needed width in the form of Jesus Navas, but City still proved wasteful when decent chances fell their way.
Aguero forced Vito Mannone to keep his focus with an effort turned around the post after the 70-minute mark, whilst substitute Edin Dzeko sent a header wide from a corner.
Sunderland rode their luck in the last ten minutes, but clung on to a crucial three points that significantly boost their chances of climbing out of the relegation zone over the coming weeks.