Liverpool's standards have been so high this season that any slip from the pinnacle will raise eyebrows - so a third loss in four games is bound to provoke questions.

Watford's 3-0 defeat of Jurgen Klopp's Premier League champions-elect was a seismic shock, given the Hornets were in the relegation zone and Liverpool had reeled off 18 straight league wins in an unbeaten season.

Indeed, they were on an unbeaten 44-match league sequence stretching back to 3 January 2019, when they lost at Manchester City.

Their latest reverse, the 2-0 FA Cup fifth-round loss at Chelsea, was not a surprise as Klopp has shuffled his pack in this competition, the game was at Stamford Bridge, and the stakes were huge for manager Frank Lampard and his players.

Throw in the Champions League last-16 first-leg defeat at Atletico Madrid, a matter that can still be put right at Anfield, and there is no doubt Liverpool are going through the kind of occasional downturn that affects even the greatest of sides.

It is simply because Liverpool wore a cloak of invincibility for so long this season - and most of last - that the reactions are more extreme, the questions slightly illogical.

Reds look lethargic

There is no doubt that Liverpool are not quite at their best at the moment, although reality suggests they could never sustain the rarefied levels they had operated at over the course of a whole campaign.

Liverpool are currently looking lethargic, one of the last words that could previously be attributed to them as their machine-like efficiency, power and skill overpowered opponents with relentless regularity.

There was growing frustration too, as exemplified by substitute James Milner's hack at Pedro as he escaped down the wing late on and Sadio Mane's angry exchange with Cesar Azpilicueta seconds before the final whistle.

Since the winter break, Liverpool have not picked up the same rhythm and tempo they had before.

They started February with a blistering 4-0 beating of a Southampton side who actually acquitted themselves well at Anfield.

Since then they have ground out a 1-0 win at Norwich City, lost in Madrid and had a narrow 3-2 victory over troubled West Ham United at Anfield, before these past two losses.

It was never going to be an untroubled stroll to the title and trophies for Liverpool this season - there would always be bumps in the road and better to find them with a 22-point lead and a place in the Champions League quarter-finals still very much on offer.

And Liverpool's display at Chelsea, with a changed side but one that still contained superstars such as Virgil van Dijk and Sadio Mane, was as decent as Klopp suggested afterwards.

It may hurt the romantics but the FA Cup has not been at the top of Liverpool's priorities this season - as proved by the young team that beat Everton in the third round and the virtual youth side that overcame Shrewsbury Town in a fourth-round replay at Anfield while Klopp and his senior players enjoyed that winter break.

Winning, though, is a habit and for the moment Liverpool have lost it.

Absent Henderson's importance highlighted

The winning habit will return, with every chance it will happen against Bournemouth at Anfield this weekend, but Klopp and his players feed off that feeling and make no mistake there was pain in this defeat, as their reaction proved.

Liverpool were undermined by Adrian's error for Willian's first goal and by the returning Chelsea keeper Kepa Arrizabalaga, who belied his previous poor form this season with a string of crucial blocks.

Klopp can take heart from the development of youngsters Neco Williams and Curtis Jones and this was not a performance on a par with the abysmal effort at Vicarage Road.

And, in his absence, Liverpool captain Jordan Henderson's importance as a leader and midfield operator has been underscored. He had his doubters even towards the end of last season but it is unlikely he will be underestimated again.

Fabinho, arguably Liverpool's best player before he sustained a knee injury against against Napoli in the Champions League in November, has not been able to regain his best form since his return to action.

The idea of Ross Barkley running from inside his own half to seal the deal is a lot harder to contemplate when Henderson and Fabinho are in top form.

Reds need to return to form before Atletico visit

Liverpool's first title triumph for 30 years is now a mere formality, a wait for the last points to be collected so the celebrations can start.

If Liverpool's character requires testing, and they have been passing pretty much every examination placed in front of them for the past two years, then it will come against the battle-hardened, streetwise Atletico Madrid and their street-fighter coach Diego Simeone at Anfield on 11 March.

Liverpool have mislaid some old certainties in recent weeks but Klopp will be confident they can be rediscovered before Simeone rumbles into town.

This past two years have seen Liverpool lose then win a Champions League final, and finish second in the Premier League last season despite losing only one game, before transforming that into a runaway triumph this term.

The Premier League title is Liverpool's but Klopp and his players will know the bumps they have experienced in the past fortnight must be smoothed out before Simeone and his players pitch up for what will be an inevitable war of attrition at Anfield.