It was a super Sunday at Old Trafford as the reds enjoyed their biggest victory over the old enemy and inflicted a joint heaviest home defeat for United.
Mo Salah scored a hat-trick, the first Premier League hat-trick by an opposition player at Old Trafford, and it takes his recent record to an astonishing 14 goals in the last 10 consecutive games.
The brutal truth of the matter was that Liverpool didn't even require top gear.
With Fabinho, Mane and Matip all out of the first team, Konate came in for his second Premier League appearance and Jota filled Sadio's spot up front.
But the reds were simply too good for a Man United side incapable of defending. Just like against Atletico, the reds had stormed into a two goal lead before 15 minutes were even on the clock.
Naby Keita opening the scoring thanks to a Salah assist, and then a wonderful sweeping cross by Trent dispatched by Diogo Jota.
Mo Salah made it three and opened his account for the day. He could have had a couple more before Ronaldo earned himself a yellow card after kicking the ball into Curtis Jones' chest.
That only antagonised the reds further and they made it 4-0 on the stroke of half-time when Salah scored again. United have never been 4-0 down at home before but this was no ordinary day for them.
Their fans began streaming home at half time - there would be no fightback from them in the second half.
Liverpool quickly made it 5-0 and Paul Pogba, who only appeared on the pitch at half time, was subsequently sent off after a nasty lunge on Naby Keita.
Becker, Alexander-Arnold, Konaté, van Dijk, Robertson, Henderson, Milner, Keïta, Salah, Firmino, Jota
Subs: Adrián, Gomez, Minamino, Tsimikas, Origi, Matip, Mane, Oxlade-Chamberlain, Jones
There was still time for a goal from Ronaldo to take the edge off the scoreline.
Sadly for United, it was offside and rightly ruled out.
The reds slipped back down the gears and saw out the game in front of a decreasing number of home spectators.
The away fans however were thoroughly enjoying the afternoon, although Ole Gunnar Solskjaer failed to heed their requests to 'give us a wave.'
Liverpool move back to second, one point behind Chelsea, but protect the only unbeaten record in the division. They now have a seven point gap over both Everton and United and the senior players will now enjoy the luxury of a day off as the reds travel to Preston for the League Cup.
What a day it was at Old Trafford. The best in recent memory.