Alexander Isak scored the winner as a largely second-string Newcastle came to life after the break to beat a much-changed Manchester City and reach the fourth round of the Carabao Cup.

Newcastle, who lost to Manchester United in last year's final, made 10 changes from Sunday's 8-0 win at Sheffield United and barely got a kick in a first half dominated by the visitors.

But with Bruno Guimaraes and Anthony Gordon sent on at the break, the Magpies were transformed, with Isak slotting home following fine work from Joelinton.

Disciplined but passive in the face of City's possessional dominance, Eddie Howe's men were fortunate to still be level after 45 minutes, with Julian Alvarez missing two decent chances.

Pep Guardiola opted for seven changes of his own, giving a first start to young midfielder Oscar Bobb among them, but the familiar patient probing was evident.

But the home side deserved their victory thanks to their second-half display, which was full of energy and endeavour and played largely in the face of a City side who could not react.

For Pep Guardiola's side, it was just a second loss inside 90 minutes in their last 38 games in all competitions.

Newcastle are now unbeaten in four games after a run of three straight losses, with their reward for Wednesday's win a fourth-round shot at revenge against the side that beat them in last year's final.

The only downside for Newcastle, with Paris St-Germain to come on Wednesday in the Champions League after Saturday's league visit of Burnley, was Isak departing the game on the hour with an injury.

Even with so many changes, the styles of these two sides and the reasons they are both so prominent in the English game now was evident in an entertaining game of two halves at St James' Park.

City looked to dominate and patiently pick apart their opponent - a process they slotted into seamlessly in the first 45 minutes without making an important breakthrough.

Bobb buzzed about and produced some nice touches, Kalvin Phillips saw plenty of the ball and recycled it neatly inside the Newcastle half and Jack Grealish gave the home defence plenty to stay vigilant about.

Had Alvarez shown the kind of predatory finishing that has defined his season thus far with two chances - the first the best of the two but saved by a Nick Pope boot - City could well be looking at a fourth-round tie of their own.

But even with a shadow side, Newcastle are a well-drilled unit out of possession and they held firm until the break before turning on the afterburners in a superb second period.

The introduction of Gordon and Guimaraes in place of full debutants Lewis Hall and 17-year-old Lewis Miley was the catalyst, but the whole Magpies side were improved.

Gone was the passivity and in its place an arrowhead of energy and intent straight to the heart of City's defence.

Isak has been brilliant in his sophomore season in England and he was on hand yet again to slot in at the back post after a driving, powerful run and low ball from Joelinton.

After that they continued to press but also managed the game superbly to hold City at bay, despite the introduction of Phil Foden, Matheus Nunes and Jeremy Doku.

The closest the visitors came to forcing a penalty shootout was a Rico Lewis shot that he dragged past the post.