Liverpool won their first three but have since lost two and drawn one, and included in that half-dozen are Champions League encounters against Paris St Germain and Napoli and two games against Chelsea.

In the same period City have won five and lost one – a surprise Champions League defeat to Lyon – although the highest-placed top-flight side they have met in that time is Brighton, currently 15th.

“It is a tough game, absolutely,” said Klopp, whose side last season drew six of their 12 fixtures immediately after a Champions League tie.

“It is absolutely intense since the last international break. We cannot change that so we have to make sure we are ready.

“We don’t have to think about intensity. We have three days to recover and then we will face Man City.

“It would’ve been difficult any way at any time of the season, it is always difficult, but let’s have a look how the players are after the game and then we will prepare.

“Then we have our crowd at our backs. You could see Napoli used the atmosphere and we couldn’t calm it down, but on Sunday it will be 100 per cent different.”

Liverpool will be hoping for positive news regarding midfielder Naby Keita before the weekend.

The Guinean, making his debut in the competition for the club he joined in the summer, lasted just 19 minutes before going to ground on the pitch and eventually being taken off on the medical cart.

Press Association Sport understands Keita was subsequently transported to a
local hospital as a precaution after complaining of severe pain.

The team have an overnight stay in Naples so Keita’s condition will be assessed again in the morning.

There is no indication yet whether the injury will rule him out of Sunday’s
top-of-the-table clash at home to Manchester City.

This weekend is the second in succession Liverpool have faced a top-three side, having drawn at Chelsea thanks to Daniel Sturridge’s late equaliser on Saturday. Both teams have 19 points and while City have a superior goal difference, their record at Anfield is unimpressive.

Liverpool have won their last six home matches against their north-west rivals and are unbeaten in 11 in all competitions, with their last defeat to City at Anfield coming in May 2003.

They have also not lost a home Premier League match since late January but are not yet close to replicating their best form of last season. Sadio Mane has not scored in his last six matches, Roberto Firmino in his last four while Mohamed Salah has found the net just once in his last seven.

Defeat in Naples will be a worry but it may be the wake-up call Klopp’s players need.

“It’s a good game to learn from. That’s what we’re going to do – we’re going to analyse the game and see what we can do better,” midfielder Georginio Wijnaldum told liverpoolfc.com.

“We know what we can bring, we still have confidence, but this was a reality check on how things must not go. It’s a good lesson for us to get better. We have to take it as a lesson and then we have to carry on.

“We have done it better this season, so we can do it – but we have to do it every game.”

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