Manchester United and Liverpool go head to head this weekend in one of English football's big rivalries - and it is as important as ever.
Both sides have rivals from the same city in the Premier League, but for many the big one is the meeting of the sides separated by 32 miles.
This is their 202nd meeting, with United winning 81 times and Liverpool 68 so far.
The last match between these sides - at Old Trafford in May - was postponed as United fans protested against the club's owners. Liverpool won the rearranged game 4-2.
United are trying to show they can compete for the big trophies this year, as Liverpool look to bounce back from last season's disappointment.
BBC Sport looks at some potential talking points.
- All you need to know about Man Utd, in one place
- All you need to know about Liverpool, in one place
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A key moment in United's title hopes?
United are sixth in the table going into Sunday's action with four wins, two draws and two defeats from eight games.
Ole Gunnar Solskjaer's side only have one point from their last three games and, if they are to challenge for the title, they must find some form quickly.
In four of the past seven seasons, the title winners have only lost two or three league games all season.
Last season, Manchester City won the title with 86 points, the lowest title-winning haul since Leicester in 2016. To even reach that amount, United need to average 2.4 points a game for the rest of the season.
Liverpool, in third place, are unbeaten - but their gap over United would only be a point if the Red Devils win.
BBC Sport's Simon Stone said: "Speak to some Manchester United fans and they are quietly optimistic about their meeting with Liverpool.
"Their team might have only won three of their past eight games but, the theory goes, Liverpool at Old Trafford is exactly the kind of game in which United's star names will excel.
"Frequent discussion about never knowing which United team will turn up really revolves around inherent weaknesses in the manager's preferred 4-2-3-1 formation.
"At the top of the pitch, the players don't work hard enough when they do not have the ball, it is claimed. That puts pressure on those behind.
"No matter which personnel are deployed, the midfield two do not function effectively as a pivot between defence and attack, which exposes issues, either technical or physical, at the back, exposing David de Gea in goal."
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Liverpool, the 'forgotten' title contenders?
There was a strange dynamic in the summer when everybody was predicting a two-way title race between Manchester City and Chelsea.
Of 20 BBC pundits, 13 tipped City and seven tipped Chelsea, with nobody expecting Liverpool to win the title.
One expert even predicted Liverpool would not finish in the top four.
But Liverpool won the 2019-20 Premier League title by 18 points - and were 33 points above third place.
They finished in third, 17 points behind City last season - but they were hindered by several defensive injuries, most notably to Virgil van Dijk.
The Dutch centre-back has now returned and Liverpool are unbeaten in 12 games in all competitions this season, scoring 36 goals.
Salah v Ronaldo - who will come out on top?
Cristiano Ronaldo's move back to Old Trafford made all the headlines this summer but he is being outshone by Mohamed Salah in the Premier League this season.
Salah has scored seven goals in eight games - including two goal-of-the-season contenders. He is joint top of the scorers list with Jamie Vardy - and joint second on assists with four.
Ronaldo, by contrast, has three goals and no assists in five games - fewer than Hwang Hee-chan, Ismaila Sarr, Callum Wilson and Neal Maupay.
In all competitions, the gap between Salah (12 goals) and Ronaldo (six goals) is starker.
Salah is known by Liverpool fans as the king - can he now prove he is the Premier League's top star?
Reds boss Jurgen Klopp said: "Why should we compare Cristiano Ronaldo and Mo Salah? Obviously both are world-class players, so that's how it is.
"I would say even when Ronaldo's left foot is not that bad, I would say Mo's left foot is probably better.
"Maybe Cristiano in the air is slightly better and the right foot is probably better. But speed-wise they are both pretty quick, very desperate to score goals - so maybe that's it."
Solskjaer said he would back Ronaldo "in any competition".
"His [Ronaldo's] goalscoring record is incredible and he just keeps on scoring. That being said, Salah, at the moment, he's on fire.
"You see some of the goals he's scored lately - we know we have to be at our best to defend against him."
What else have the managers said?
Solskjaer is yet to beat the Reds in the league as United boss, while Liverpool's recent form has them unbeaten in 21 games overall dating back to April and they've scored three goals or more in their last eight away matches in all competitions - including this week's 3-2 victory over Atletico Madrid.
Solskjaer said: "It's going to take everything to get a result against one of the best teams in Europe and the world.
"They are one of the teams we are trying to chase, because what they have done in the last four years is something we are striving towards and to go past them.
"We did end up above them last season, but they had a very bad spell of injuries and now they are back to their best."
And after ex-Manchester United midfielder Paul Scholes claimed Klopp would not fear Manchester United, the Liverpool boss said: "There was not one second when I was rubbing my hands together watching that game. You could see Atalanta caused United problems but the second half was a pure power presentation from United."
Klopp added that he's been preparing his side for a "tough game against a really good opponent" and said "we all know United can do incredible stuff".
'Win your battles': Focus on United's duels stats
Andrew Bassett, BBC Sport data analyst
In Manchester United's last league match, a 4-2 defeat at Leicester, they were outrun by the Foxes by a significant margin, with 110km of distance covered compared to 105km.
When pundits talk about 'winning your battles', we can put a figure on it by duels won. This is a measure of which team won the 50-50 contests during a match.
Last Saturday was a good example of this; United's duels-won figure went from 46% in the first half to 37% in the second. Leicester came out on top in the second half by winning nearly two-thirds of the duels, making their dominance count with three goals in the final 15 minutes to win the game.
What's worrying for United is this is no one-off. United have the joint lowest duels-won figure in the league this season, with 47% from their eight matches so far.
Protest issues have not gone away - analysis
Simon Stone, BBC Sport
On 18 October, Manchester United confirmed that Kevin and Edward Glazer had raised $161.31m (£116.97m) through their share sale in Manchester United.
Three weeks earlier, Joel Glazer attended his second fans' forum in just over three months - after never previously going to one in the 16 years of his family's ownership of the club.
While the visit of Liverpool to Old Trafford is a stark reminder of the trouble that caused last season's game to be called off after fans broke into the stadium and spilled onto the pitch, breaking Covid restrictions in the process, the two matters involving United's owners are related.
Joel Glazer broke his silence after the debacle, which was triggered by a combination of long-standing disenchantment with the owners and the fallout from the doomed European Super League project.
One of the key demands made by supporters was for greater fan involvement. To that end, Glazer is working with the Manchester United Supporters Trust (Must) to put together a share scheme.
But it remains true that - for the Glazers to leave - it will take some very rich individuals to invest. And this would be into a club which now has three domestic rivals - Manchester City, Chelsea and Newcastle - who have access to substantial funds, which suggests anything like a repeat of the sustained glory days enjoyed under Sir Alex Ferguson will be tough.
Further mass demonstrations are not anticipated this weekend. But the problems at Manchester United have not gone away.
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