Ole Gunnar Solskjaer's side, who have endured a rocky start to their season, now have six points from two games after building on their impressive opening win against Paris Saint-Germain

United took the lead midway through the first half when Marcus Greenwood, 19, received a through ball from Paul Pogba and stroked the ball across Peter Gulacsi and into the far corner.

Substitute Rashford struck three times after coming on in the 63rd minute to remind Solskjaer he is the main man at Old Trafford.

Anthony Martial also got in on the act, scoring a penalty on an outstanding night for the three-time European champions, who are now three points clear at the top of Group H.

Greenwood, who last month was sent home in disgrace by England for breaking coronavirus protocols, started up front alongside Martial, with Rashford and Bruno Fernandes surprisingly left on the bench.

Leipzig started brightly, pinning the home side back but United soon settled.

Fred forced an early save before Luke Shaw had a shot blocked by the head of Yussuf Poulsen and Martial burst into the box but failed to find Pogba.

The home side broke the deadlock when Pogba drove forward from midfield and found Greenwood, who had timed his run into the box perfectly and hit his shot with unerring accuracy.

United had a nervous wait as VAR looked at a potential off-side but the goal was allowed to stand.

Leipzig came back strongly, pinning United back for long spells of the rest of the first half.

United had an appeal for a penalty soon after the break when the ball hit Ibrahima Konate's arm but a VAR check ruled there was no penalty.

United goalkeeper David de Gea produced a sharp save to keep out a Konate effort at the back post from a tight angle after the ball was flicked on by Poulsen.

The visitors, now with substitutes Marcel Sabitzer and Alexander Sorloth on the pitch, were playing with urgency but United looked dangerous on the break.

Fernandes sent a superb first-time ball through to Rashford, who raced through and slotted past Gulasci.

The linesman had raised his flag for offside but VAR checked the decision, ruling that the forward started his run in his own half and awarded the goal.

Rashford rifled home again four minutes later to make the score 3-0 but unselfishly allowed Martial to take the penalty after the Frenchman was brought down in the box.

But the England man completed his hat-trick in added time to cap a devastating display.

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