Liverpool are 21 matches into their Premier League title bid and, remarkably, have failed to win just once.
Jurgen Klopp's side look unstoppable as they charge towards a first top-flight championship since 1989-90, building a 14-point lead – with a game in hand – heading into this weekend's fixtures.
But the one team to halt Liverpool this term, holding the Reds to a 1-1 draw at Old Trafford on October 20, were bitter rivals Manchester United.
Only a late Adam Lallana equaliser to cancel out Marcus Rashford's opener maintained the leaders' unbeaten league campaign.
United face Liverpool again on Sunday, visiting Anfield, so we take a look at what went right for Ole Gunnar Solskjaer's men last time and what they must do to earn a result again on Merseyside.
MIDFIELD BATTLE KEY
The supposed weakness of this Liverpool team is said to be in their midfield, and while that often does not bear true, it did in the reverse fixture.
The Reds boasted 68 per cent of possession but captain Jordan Henderson endured a rare tough afternoon, completing just 23 passes as he was first shifted out wide and then replaced by Lallana.
Andreas Pereira was key for United in leading the sort of harrying often associated with Klopp's early Liverpool teams, not allowing the visitors to settle and winning possession on 11 occasions. The Brazilian (11.89km), compatriot Fred (11.92km) and Scott McTominay (11.93km) also each covered more ground than any other player.
But if the centre of the pitch is where Liverpool can be got at, it is also where United are now short. Pereira's form has been ordinary, Fred is inconsistent, and both McTominay and Paul Pogba are injured.
WING-BACKS A WINNER
As well as pressing the Liverpool midfield back, Solskjaer crafted a plan to combat the dual threats of right-back Trent Alexander-Arnold and left-back Andy Robertson in October.
A five-man defence allowed Aaron Wan-Bissaka (two tackles, two clearances, two interceptions) and Ashley Young (three clearances, two interceptions, two fouls won) to aggressively match up against their opposite numbers, limiting the effectiveness of two of the division's chief creators.
Liverpool mustered just seven crosses from open play in the first half, while only four of the 19 deliveries Alexander-Arnold and Robertson attempted between them by full-time found a team-mate.
Unfortunately for United, the lax marking of their central defensive three saw Lallana left free to convert when Robertson did hit the mark late in an improved second half. The Red Devils cannot afford similar such lapses this time.
SALAH STAYING SILENT
If the midfield is stifled and Alexander-Arnold and Robertson are kept in check, Liverpool will be left hoping for a moment of magic from a key attacking star like Mohamed Salah.
But Salah, who missed out with injury at Old Trafford, has not scored or assisted a single goal in four Premier League appearances against United.
That might sound like a run destined to be broken soon enough, but the same could be said of Raheem Sterling's unlikely drought. The Manchester City forward is now scoreless in 18 meetings with his club's city rivals in all competitions.
Salah's continued struggles in a fixture that brings plenty of pressure would represent a big boost as United look for all the help they can get at fortress Anfield.
MAN FOR THE BIG OCCASION
That Old Trafford stalemate provided yet more evidence that Solskjaer can get his team to turn up in the big matches.
United have won away at Tottenham, Arsenal, Chelsea (twice), Paris Saint-Germain and Manchester City since Solskjaer took charge 13 months ago, while Liverpool have now been held twice at Old Trafford.
Indeed, Solskjaer is the only manager Klopp has faced more than once in the Premier League and failed to beat.
But after back-to-back victories against Spurs and City last month lifted the United boss, his side lost to Arsenal and Pep Guardiola's men in the New Year. With a modest record against lesser opposition, Solskjaer must again prove his worth in these contests.