While manager Jurgen Klopp has been reluctant to call his team’s recent upturn in form a genuine comeback, the Reds rolled back the years at the expense of their greatest rivals.
As was so often the case during the glory years under Klopp, Liverpool flew out of the blocks and looked particularly dangerous through Salah, who was guilty of dragging his shots wide in the opening few minutes.
United, on the backfoot for the opening 30 minutes, did manage to grow into the game as the first-half went on and could well have had an opener through either Bruno Fernandes or Marcus Rashford. They, however, fluffed their lines from close range.
Five minutes before the break, Gakpo struck. Fizzed in a fierce ball from Andy Robertson, the Dutchman got in-behind Fred and away from the covering Raphael Varane before unleashing an emphatic finish across David De Gea.
Still, United would have gone into the break confident of springing a comeback, much as they did against Barcelona only a matter of days ago.
Liverpool would soon put an end to that. Minutes into the second-half, Nunez headed home before United collapsed.
Gakpo drifted in and dinked a sublime finish over De Gea to put the hosts three ahead before Salah – who certainly has previous in the fixture – made it four with a lethal strike after a Liverpool counter.
By the time Nunez towered above the United defence to head in his second, it all felt rather like the frankly bizarre Ralf Rangnick era for the travelling support. When Salah’s second made it six, and him the club’s all-time top Premier League goalscorer, it somehow felt worse.
Such was United’s apathy, Roberto Firmino managed to find the time to add a seventh, capping off an emotional week in which he announced the imminent end of his Liverpool career.
For all the progress this United team have made under Erik ten Hag this season, their capacity to capitulate is seemingly constant.
Liverpool move within three points of the top four, while United are once again looking over their shoulders. How quickly things can change.