Liverpool ran riot at the Etihad Stadium this evening as they smashed Manchester City 4-1.

The Reds raced in to a three goal lead inside half an hour, thanks to a Mangala own goal and then a goal a piece between Philippe Coutinho and Roberto Firmino. Sergio Aguero pulled one back for the hosts with a wonderful curling finish from 20 yards just before the break, but Martin Skrtel rifled in an unstoppable fourth to complete the rout in the second half.

It was the Brazilian duo who ran the show for Liverpool in the first half, with Lucas and Adam Lallana also impressing for Jurgen Klopp's side.

Manuel Pellegrini's City just couldn't handle Liverpool's pace going forward and looked lost in defence without captain Vincent Kompany at the back.

So here are three things we learned from that incredible Liverpool win at the Etihad...

Klopp is a tactical genius

KloppLFC

But we already knew that, didn't we?

Klopp's decision to play a false nine at Chelsea paid off as his side ran out comfortable 3-1 winners at Stamford Bridge.

And he did the same again today, with Roberto Firmino and Philippe Coutinho making all the difference going forward, particularly in the first half.

It's tactical moves like that that catch teams by surprise, especially when you've got the likes of Christian Benteke fit and raring to go and Sturridge returning from injury.

But Klopp got it bang on again today.

Coutinho & Firmino have arrived

The Brazilian duo ran the show in the first half and look like they've finally clicked as a pairing at Liverpool.

Firmino took some time to settle in after arriving from Hoffenheim in the summer and Coutinho was having a difficult spell up until his two goal showing at Stamford Bridge a few weeks ago.

Both combined for each of Liverpool's three first half goals, combining well in the build up to Mangala's own goal and then taking turns to set each other up for a goal each inside the opening half an hour.

Liverpool fans will be hoping Coutinho's injury, which forced him off in the second half, isn't too serious.

Man City miss Kompany...

Man City rarely concede, so to see them ship four goals - three in just 20 minutes on home soil - will be an alarming issue for Manuel Pellegrini and the Etihad faithful.

They just didn't look sure enough at the back without captain Vincent Kompany. The Belgium international always adds that little bit extra solidity in defence when he plays, but City just didn't have that with Mangala and Demichelis this evening.

However, Liverpool fully deserved their win and completely overran City in the first half to claim a 3-0 lead before Aguero pulled one back just before the break.

But City will be desperate to get Kompany back as soon as possible to ensure there isn't a repeat of such an awful defensive showing. The fact is, there