Sergio Aguero's work here is done. Two goals and an assist. That'll do. On comes Kelechi Iheanacho for a rare appearance. 

Sterling is absolutely lightning over open ground. A ball forward from Clichy looks to be way too heavy, but Sterling turns on the afterburners and catches it just ahead of the byline. His team-mates aren't quite as quick, though, and the cross finds only space.

Boos from the Town fans for Fabian Delph because of his Leeds connections. He is on for Kevin de Bruyne.

If it wasn't over before, it is now. An emphatic Sergio Aguero first-time finish at the near post, from Raheem Sterling's low cross, makes it 4-1 and books City a last-eight showdown with Middlesbrough.

Rajiv van La Parra does well down the left and plays in a dangerous low ball but Gael Clichy is there ahead of Tommy Smith to hammer the ball clear.

After a break in play for a head injury to Jon Gorenc Stankovic (he's fine) play continues, but the intensity has dipped. The Town players look tired from chasing and City look content to preserve some energy and keep possession.

A nice freekick saved well by Joel Coleman, why not take a look again.

Town's final change sees the impressive Philip Billing depart, with Jonathan Hogg coming on. 

Raheem Sterling thinks he should have a free-kick after getting behind his marker and tumbling to the ground. The referee isn't fooled, though.

De Bruyne opts to chip in a cross from the free-kick. It is a good ball but skips just in front of the advancing City men in the box.

City win another free-kick in Town territory, this time when Gael Clichy is tripped. Town looking tired now.

De Bruyne hots the free-kick and it is heading for the bottom corner until Joel Coleman dives to palm it behind.

The resulting corner is headed away at the near post.

City free-kick, 10 yards outside the box...

Another change for Town. Joe Lolley off and Tommy Smith on. Smith is another who used to be in the City academy.

Now it is Town's turn to feel aggrieved at a referee's decision. Collin Quaner breaks away down the right and into the box and turns back inside before tumbling having received a tiny bit of contact from John Stones. I've seen them given.

Simon Stone
BBC Sport at the Etihad Stadium

Kelechi Iheanacho is warming up for Manchester City.

The Nigerian scored 14 goals in his debut campaign last season, and got three in three games at the start of this term, including a goal at Manchester United in September.

He has been used sparingly by Pep Guardiola recently though, making two appearances in 2017 and none since 15 January.

Some breaking news from Barcelona - Luis Enrique has announced he will not continue as manager next season. Click here for more on this story.

It should be 3-2. The corner is taken short to the sub Van La Parra, who swings in a superb ball that Joe Lolley heads over. He was in space. He should have scored. 

Image source, Reuters

Off goes Harry Bunn, on comes Rajiv van La Parra.