The full-back, who edged himself back into the affections of Black Cats fans with the opening goal in Wednesday night's Capital One Cup win over Southampton, did it again to secure another 1-0 home win against City, the same score as in the past three seasons.
The visitors started positively and Bardsley had to make an important header to deny Alvaro Negredo a seventh-minute header at goal from Aleksander Kolarov's cross, and Mannone plucked James Milner's long-range drive out of the air seconds later.
But they were soon ahead. Wes Brown, starting his first Barclays Premier League game since January 21, floated the ball over the top for Bardsley to shake off Milner before cutting inside and curling a shot across goalkeeper Costel Pantilimon, once again preferred to England international Joe Hart.
City's response was tepid and Sunderland created a series of half-chances to increase their lead, although Ki Sung-yueng overhit a through-ball to the unmarked Fletcher and defender Martin Demichelis got to Emanuele Giaccherini's 36th-minute cross marginally ahead of the Scot.
Winger Jesus Navas was sent on after the break, and the newcomer almost made an immediate impact, slipping past Johnson and crossing for Negredo to send a looping header over.
Navas might have equalised himself within five minutes of his arrival when Sergio Aguero out-paced John O'Shea and pulled the ball back to him, but Bardsley made a vital block.
Poyet's men were forced to weather a relentless assault as the final whistle approach, but with Brown marshalling his forces outstandingly at the back there was simply no way through for City.