Eddie Howe made four changes from Wednesday’s 2-1 win over Manchester United. As a reward for his late winner, Will Osula led the line and Nick Woltemade returned from illness.
Joe Willock and Sven Botman also came into the starting line-up as Anthony Gordon, Joelinton and Dan Burn dropped to the bench, while Jacob Ramsey dropped out altogether due to suspension.
Harvey Barnes gave the Magpies the lead in the 18th minute when he was found by Sandro Tonali to race forward and coolly finish into the top corner past James Trafford.
The strike ended a run of 12 matches without a goal for Barnes, whose last came in the third round win over AFC Bournemouth.
Newcastle dominated the opening 25 minutes but faced relentless Man City pressure from then until half-time, as Savinho equalised in the 39th minute.
It was more of the same in the second half as Omar Marmoush put the visitors ahead when he got on the end of Matheus Nunes’ cross to the back post.
Marmoush then put the tie out of Newcastle’s reach with his second and Man City’s third in the 65th minute.
Here are our Newcastle United player ratings:
Misplaced a pass in the box in first-half stoppage time and was indebted to Joe Willock for making a last-ditch challenge. Didn’t get anywhere near Man City’s three goals.
1. Aaron Ramsdale - 5
Misplaced a pass in the box in first-half stoppage time and was indebted to Joe Willock for making a last-ditch challenge. Didn’t get anywhere near Man City’s three goals. | Getty Images
Defended well in the main but couldn’t stop the cross that led to Man City’s equaliser. Ended up on the floor as Omar Marmoush made it 2-1.
2. Kieran Trippier - 6
Defended well in the main but couldn’t stop the cross that led to Man City’s equaliser. Ended up on the floor as Omar Marmoush made it 2-1. | Getty Images
Had some nervy moments in the second-half as Man City piled the pressure on Newcastle’s backline.
3. Malick Thiaw - 5.5
Had some nervy moments in the second-half as Man City piled the pressure on Newcastle’s backline. | Getty Images
Part of a defence that shipped another three goals at St James’ Park.
4. Sven Botman - 6
Part of a defence that shipped another three goals at St James’ Park. | Getty Images