You can see highlights of Liverpool v Man Utd on Match of the Day 2 at 22:45 BST on Monday on BBC One and the BBC Sport website.
Liverpool have not gone into many recent games against Manchester United as favourites. They do on Monday, but only just.
United have won their past four meetings in the Premier League, but the mood feels different at Anfield at the moment.
Liverpool have made a great start to the season and their manager Jurgen Klopp deserves huge credit for that because I did not think they would have progressed so much as a team, so early in the campaign.
They are playing exactly how Klopp wants them to – their tempo is good, their pressing is great, and everyone seems to be on the same wavelength.
Klopp’s side looks pretty well balanced. They have been playing on the front foot and going after teams, with real freedom and impressive creativity.
They thoroughly deserve to be where they are in the table right now – the question is where will they end up?
Mourinho has got history at Anfield
This game is a great yardstick for Liverpool’s prospects this season because, although United’s recent form has been mixed, they have got some brilliant players and possess enough quality to win any game.
Then there is United manager Jose Mourinho, who has a pretty decent record at Anfield too of course.
There is every chance his United side could go to Liverpool and frustrate them in the way his Chelsea teams have got results at Anfield in the past.
The Blues’ 2-0 win in 2014 that stopped Liverpool from winning the title is the most famous of his wins there and, domestically, Mourinho has only been beaten once in eight visits.
United are well capable of doing something similar, but the difference this time is what they will have to contend with, because this Liverpool side are absolutely flying after winning five games in a row in all competitions.
The Reds are full of confidence and will go on the attack. Defensively it is going to be a real test for United, who are going to have to play really well to leave Anfield with anything.
Time to start talking about Liverpool for the title?
Liverpool have already gone to Arsenal and Chelsea and won this season, and drawn at Tottenham too. If they can get a positive result on Monday, then Reds supporters will really start to believe they have a chance of winning the title.
Not many people thought that at the start of the season, but if you win these big games – like Tottenham did against Manchester City before the international break – then they start to take notice.
Liverpool’s home form will be a factor in that too, and that has already shown signs of improvement.
Last season they got some great results on the road under Klopp but struggled when teams came to Anfield and put men behind the ball.
That has not been the case this time around – they have scored nine goals in two games at home so far.
It is still very early of course and they might not quite be at the stage where they are contenders but even talking about it is a sign of how far they have come since Klopp took charge 12 months ago.
Even if their form does dip, then fans can still see a definite identity and improvement in the way the team plays and the quality of the squad and, this season, that is all they wanted.
The fact Klopp has had a pre-season with the squad has made a massive difference but the key to Liverpool’s good start was integrating the new players that were brought in over the summer.
Sadio Mane has been exceptional in attack but all of them seem to have settled in, which is a massive bonus.
There are doubts when you sign anyone, even if you know the player and his personality well, because playing for a big club brings its own pressures.
A pivotal moment for United’s season?
Even if Liverpool lose on Monday, they will still have made a better start to the season than was expected.
It is not the same for United, which is why I think this is actually a bigger game for them.
They have had some mixed results in the league in recent weeks and, if they are beaten at Anfield, they will not just lose ground at the top of the table, they will lose confidence.
People will start doubting them as credible title contenders and, as a player, those doubts can come into your head too.
It is understandable why they have been up and down. Mourinho only took charge in the summer and is taking a bit of time to assess his squad, realise who is best in which position and who plays well together.
He is doing what Klopp started doing a year ago, which is trying to find the best 11 players to suit the way he wants to play.
United will get better – I still feel Mourinho has the quality and strength in depth in his squad to mount a challenge this season but that will depend on whether his players can take on board what he is asking them to do quickly enough for them to stay in touch with the leaders.
That is why this game is pivotal for them and it will be fascinating to see how United approach it, because I don’t think Mourinho will just park the bus.
Liverpool still have work to do at the back
I have a feeling United might be cautious early on, but they will have a go at Liverpool at some point in the game because that is what is expected of them, and Mourinho knows it.
That might play into Liverpool’s hands, because it will allow them to counter-attack, but Klopp’s side are far from solid at the back.
They have problems defending set-pieces, and I don’t think Klopp knows his best back five yet – he has some work to do there.
It looks like another of their summer signings, Loris Karius, is going to be his new number one goalkeeper instead of Simon Mignolet, but he has also been changing his centre-halves, partly because of injury.
What Klopp needs to do is decide on his best line-up at the back and stick with it because the more often they play together as a unit, the better drilled they will become.
Klopp will have time to work on defending set-pieces in training because Liverpool are not in Europe and do not have the crazy schedule – Christmas and New Year aside – that he had to put up with last season when they reached the final of the Europa League and the League Cup, and played 63 games.
I would expect to see some improvement defensively soon but the way his side play, the opposition will always get chances.
When you play on the front foot, you are invariably more open at the back too. You cannot throw men forward and not expect to give away chances.
A special occasion under the lights
I have been a Liverpool supporter and player in matches with Manchester United and the atmosphere is always incredible – there is an intensity about the game that you do not get every week.
It will be difficult for the players on both sides who have not played in this fixture before to try to anticipate what it will be like because it is different to any other match.
A lot of them will have experienced other derbies but they still have to gauge the enormity of this rivalry, because it means so much to both sets of fans.
I remember as a Liverpool player the effect it had on people around the club when we won – there was a real buzz about the place.
Everyone was so happy because we had beaten ‘the Mancs’, and I am sure everyone at United was the same when they won.
The lack of local lads in both teams at the moment is a shame, because it always means a bit more when there are some involved, but that does not change the fact the fans just want the right result.
There will be a fantastic atmosphere on Monday night. Any game under the floodlights at Anfield is always special but a night game against United? It does not get much better than that.
Danny Murphy was speaking to BBC Sport’s Chris Bevan.
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