At half-time a flock of seagulls swooped down, weaving intricate patterns as they flew just above the pitch, presumably hunting afternoon snacks. Unfortunately for Sunderland, Manchester City proved similarly mercurial and almost equally elusive – not to mention hungry – on an afternoon when the excellent David Silva and friends left David Moyes’s players chasing shadows.

Well before the final whistle accomplished finishes from Sergio Agüero and Leroy Sané nudged the bottom-placed Wearsiders closer to the Championship. Six points shy of 17th-placed Crystal Palace, Moyes’s horizon looks almost as grim as Guardiola’s is bright.

A seventh win in eight games in all competitions ensured the Spaniard’s team moved up to third, eight points behind the leaders, Chelsea. Although City’s title chances seem purely mathematical, fears they could end the campaign outside the top four appear thoroughly assuaged amid newly upbeat mood music.

“I’m delighted because these are often the most difficult types of games,” said Guardiola, who embraced every City player at the end – with a special hug reserved for Silva. “I know the players better and they know me better now. I’m feeling we’re now playing quite good and that’s why we’re making results.”

Moyes recently attended City’s 5-3 Champions League game against Monaco and was so impressed that he likened Guardiola’s side to “a finely tuned orchestra”. The Scot readily concedes his own team – and redundancy-hit club – are “gasping for air” but Sunderland started promisingly enough here. In full‑on spoiling mode they closed City players down at every opportunity with Didier Ndong initially making a fine job of, at times, pressing a slightly affronted looking Yaya Touré into submission and Jermain Defoe striking a post.

Sensing opportunity 25 yards out, the former England striker swivelled sharply before anyone could shut him down and unleashed a dipping, first-time shot which bounced in front of a wrong-footed Willy Caballero before hitting the base of the upright.

Fabio Borini headed wide from the rebound when he might have rewarded his team-mates’ impressive intensity but, despite all this commendable effort and temporary success in reducing City to scrappiness, Sunderland remained far too slapdash, consistently forfeiting possession much too cheaply.

Although Jordan Pickford – Moyes’s highly coveted young goalkeeper and a player who may interest Guardiola in the summer – had surprisingly little to do in the first half he watched in horror as Sané deceived Billy Jones only for the youngster to overhit his cross. It left Silva, unattended and waiting for what seemed a simple tap disbelieving, but such disappointment did not endure.

Shortly afterwards Touré switched into dynamic mode, mopping up a poor clearance from Caballero – whose kicking was not great – and powering up‑field before setting Raheem Sterling up for a run and low cross. Having taken a slight deflection that centre was dinked, adroitly, beyond Pickford by Agüero with the hovering Lamine Koné thoroughly confounded.

That most subtle flick of Agüero’s boot represented both City’s first shot on target and a crunching blow in the solar plexus for Moyes who, until then, must have been cautiously satisfied about Jones’s attacking success against Gaël Clichy and would have been heartened to see the right-back twice come close to scoring from corners. It could have been worse for Sunderland’s manager as Silva believed he had scored on the brink of half-time only to see his “goal” disallowed for an offside against Sterling.

Early in the second half Pickford showed off enviable reflexes, saving well from Silva but, undeterred, Guardiola’s captain, simply manoeuvred himself into space, met a through ball, changed pace and advanced rapidly before playing in Sané.

Sunderland v Manchester City: Premier League – as it happened Read more

Displaying coruscating pace, Sané burnt off Jones – who had otherwise played so well – before beating Pickford with a shot which went in off the inside of the far post. It was his sixth goal from eight first XI attempts on target.

“Sané’s so fast when he runs in behind defenders,” said Guardiola, who is seeing his £37m summer gamble vindicated. “We’re so satisfied. He was expensive before but cheap now.” Team-mates rightly rushed to congratulate the former Schalke04 winger but on a day when his dribbles helped undo Sunderland, Silva’s role should not be underestimated. “David’s fantastic, a fighter,” said an approving City manager, who could also reflect on some reassuring defensive solidity from Aleksandar Kolarov.

Locals streamed towards the exits as their City counterparts serenaded Guardiola but at least Moyes’s players refused to accept it was all over. Indeed Seb Larsson, Koné and Adnan Januzaj all might have scored before Defoe briefly believed he had capitalised on City’s dead ball vulnerability by heading in a corner only to see it ruled out for offside.

At the other end, Pickford enjoyed better luck, leaving Guardiola sitting up and taking notice after saving brilliantly from Agüero.

“We tried to stop City and my players gave everything but we were under so much pressure,” a defiant Moyes said. “If we keep playing like this, though, we’ve a good chance of staying up.