Dalglish's son loved the contrast between him and Fergie as Salah made it 5-0

It was smiles all round when Mohamed Salah completed his hat-trick just four minutes into the second half, poking the ball home after latching onto Jordan Henderson's superb through ball.

Salah's earlier goals in the first half saw the Reds go three and four up, while strikes from Naby Keita and Diogo Jota put them in control.

Being 5-0 up at your biggest rival understandably sent the Liverpool fans into ecstasy and club legend Sir Kenny Dalglish couldn't contain his excitement.

And his son, Paul, seemed to revel in the contrasting reaction of legendary United boss Sir Alex Ferguson, who cut a completely miserable figure as Salah celebrated with his teammates.

Sir Alex, though, didn't take the leaf out of the books of a number of Man United fans, who took it upon themselves to leave the ground shortly after Paul Pogba was sent off for a high challenge on Keita.

That proved to be the final goal in an extraordinary clash at Old Trafford.

However, the result will only raise further questions about manager Ole Gunnar Solskjaer, who went into the match under pressure.