SCORERS: Manchester City - Silva (38), Aguero (90)
City were hanging on to a 1-0 lead with the Magpies going for broke when the Argentina international struck in stoppage time to end the home side’s hopes.
David Silva had fired the visitors into a 38th-minute lead, making the most of Edin Dzeko’s intelligent back-heel, and Manuel Pellegrini’s men will feel they were good value for the points after creating the better chances, although the result remained in doubt until Aguero struck.
Their movement and passing were characteristically impressive – their finishing less so – although Newcastle were unable to work City goalkeeper Joe Hart to any real extent despite enjoying their fair share of possession.
New boys Jack Colback and Remy Cabella were impressive on debut, while lone striker Emmanuel Riviere showed flashes of his talent before fading as he found himself locked in a physical battle with Vincent Kompany.
But while there were positives for Newcastle manager Alan Pardew and appreciative applause from the home fans on the whistle, it was Pellegrini and his club’s followers who were wearing the smiles.
Captains Fabricio Coloccini and Kompany, along with former Sunderland goalkeeper Jimmy Montgomery, laid wreaths on the centre circle as they were joined by relatives of fans John Alder and Liam Sweeney, who died on Malaysia Airlines Flight MH17.
But while City played their full part in an emotional start to the afternoon, they ripped into their hosts from the off and might have established a commanding lead within the opening 11 minutes.
Goalkeeper Tim Krul had to be at his most alert to keep out Dzeko’s close-range second-minute effort after Steven Jovetic had played him in over the top with a delicately lofted pass, and the Dutchman was in action once again nine minutes later.
Samir Nasri and Aleksandar Kolarov played a long-range one-two before the Frenchman teed himself up to unleash a rasping drive which Krul had to dive full-length to turn away.
But as they warmed to their task, the Magpies started to make an impact.
Coloccini and central defensive partner Mike Williamson managed to get to grips with Dzeko and Jovetic to allow the men in front of them to prosper, although while there were flashes from Cabella and Riviere and a series of surging runs by Moussa Sissoko, there was little of note to trouble Hart.
Cabella drifted a chipped 16th-minute effort over Hart’s crossbar and Riviere, who showed plenty of endeavour but slightly less composure, scuffed wide from distance and blazed across goal when he might have done better.
At the other end, Williamson denied Jovetic with a perfectly timed block, but the respite was temporary and City took the lead with seven minutes of the half remaining.
Coloccini and Williamson were both drawn to Dzeko as he chased down a long ball, and both were left stranded when he cleverly back-heeled it between them for Silva to exploit the space and fire left-footed past Krul.
Newcastle responded in determined fashion immediately after the restart with Yoan Gouffran seeing two shots blocked in quick succession after Colback’s 50th-minute corner reached him beyond the far post, and Cabella scooped over under pressure from Sissoko’s pass.
Full-back Paul Dummett headed over after reaching Colback’s corner ahead of Hart, but it took a good block by Coloccini to prevent Jovetic from extending the visitors’ lead on the hour.
Dzeko headed on to the roof of Krul’s net 25 minutes from time and Yaya Toure, who endured one of his quieter afternoons, floated a free kick just over eight minutes later.
The Magpies threw caution to the wind as time ran down and substitute Ayoze Perez’s shot was deflected just wide of the far post before Sissoko blazed wastefully over at the death.
But substitute Aguero wrapped up the win in stoppage time when, after Krul had blocked his initial effort, he stabbed the rebound home from close range.
Afterwards Pellegrini praised his players for maintaining their concentration levels as their legs began to tire.
City failed to keep a clean sheet during their pre-season friendly campaign and succumbed 3-0 to Arsenal in the Community Shield, so Pellegrini was pleased to see such resolution at the back.
“The players were both hungry and humble,” he said. “We need both those things if we are going to continue winning titles and if we want to improve on what we did last year.
“It was so important to me that the players had that attitude from the beginning to the end of the game.
“We were very solid at the back and Joe Hart didn’t have any problems and in the second half it was normal that we were starting to get tired.
“The players are not able to play 90 minutes at the moment but we continued with our attitude and scored the second goal.”
Despite watching Newcastle suffer a defeat that sent them to the bottom of the fledgling table on goal difference, manager Pardew was impressed with what he saw from his new-look team.
He handed five players their debuts and singled out former Montpellier schemer Cabella for praise.
“It was frustrating for us because in the second half we really pushed on up and put some younger players on, who were a bit naive at times but who threatened with their pace,” he said. “We just couldn’t get that equaliser.
“If we could have got that then we could have gone on to win it because we looked like we had more legs in the team.
“We were brave, we went for it and there were some outstanding performances. All the players were solid and Remy gave us some moments around the box that we haven’t had for a long time.”