Liverpool 2 Manchester United 0
It may have been the 195th meeting between the two biggest rivals in English football, but it was the first time the giants had come head to head in a European competition.
The red of Liverpool gained the upper hand as they won the first leg against a United side that lacked any conviction and had keeper De Gea to thank for keeping the scoreline down to two.
Van Gaal had recalled Fellaini, Varela and Schneiderlin to the side in place of Darmian, Carrick and Herrera who would all start on the bench. There was also a recall for Bastian Schweinsteiger as a substitute.
Here was the United starting XI: De Gea, Varela, Smalling, Blind, Rojo, Schneiderlin, Fellaini, Memphis, Mata, Martial and Rashford.
Mata was once again given the honour of captaining United even though Smalling was on the pitch.
United got the tie underway attacking the Kop and straight from the off they almost grabbed the opener as Memphis delivered a cross that evaded the defenders, but the onrushing Rashford was slightly caught by surprise and the ball rebounded off the young forwards knee.
The match started at a very lively pace with both sides up for the fight, heavy challenges set against a great atmosphere generated by both sets of fans.
United enjoyed the majority of the possession in the opening quarter of an hour, but as usual created little or no chances of note.
The goal buoyed the home side and in the next attack they would have gone 2-0 up, but for the brilliance and athleticism of De Gea who saved Coutinho's certain tap in right on his goal line. That save could literally turn out to be United's lifeline in the tie for if the home side had scored a second so quickly it could have been game over.
De Gea came to the rescue again for his side on thirty minutes when he made himself big in front of Sturridge to block the striker's shot.
The awkward style of the returning Fellaini earned United a free kick opportunity in a dangerous area which was fired in by Memphis with a disappointing end as it sailed harmlessly wide.
United's free kicks have been woefully poor this season with the exception of Mata's effort against Watford. But it's a sad state of affairs when they can't even get the efforts on target compared to the past when you knew something was going to come from them.
Rashford became the second United player to be booked on the stroke of half-time after a rash challenge on Moreno's.
Half-time and United trailed 1-0 without having a shot on goal. They had De Gea to thank for not going in at least three goals to the worse as he produced three saves that could have a massive bearing on the tie overall. And he did manage to get his fingertips to the penalty, however, not enough to prevent the ball going in.
It's fair to say that United would have to be the happier of the two sides to be only down by one goal. They were playing a dangerous game by sitting back and allowing Liverpool to come at them. An improvement of huge proportion would have to be seen in the second half if the Red Devils were to get anything out of this game.
At the start of the second half van Gaal made a tactical substitution in an attempt to get his team back into the game by replacing Rashford with Carrick. The change meant that Smalling, Rojo and Carrick played in a back three formation with Blind and Varela as wing backs.
David De Gea produced another high class save as he tipped over a powerful long range effort from Coutinho.
United's new formation looked to be paying off as they enjoyed a long spell of possession and applied pressure on the Liverpool defence without creating the killer ball needed to grab the vital equaliser. Martial came the closest during this spell as he almost got his head to a cross by Varela.
Fellaini became the latest United player to be cautioned for a swing and miss with his leg at Clyne.
Memphis almost threaded the ball into the path of Martial but the ball fell a little behind the French striker. However, this was better play from the visitors.
Liverpool wasted two golden chances to extend their lead as first Henderson blasted a great chance well wide then Coutinho blasted a free kick towards goal clearly not realising it was indirect.
As the game entered the final twenty minutes Firmino doubled the home side's lead when he beat De Gea with a close range tap-in following a poor attempted clearance from Carrick. All United could hope for now was damage limitation and an away goal to take back to Old Trafford.
Bastian Schweinsteiger made a much welcome return when he came on along with Herrera for Mata and Schneiderlin for the last ten minutes.
The match ended with Liverpool on top in the tie and in the driving seat against a United team that had nothing to offer in any way, shape or form.Two errors of judgement by Memphis and Carrick cost their side dearly and add to that only one shot on target it was no wonder they lost.
It doesn't look good for the upcoming FA Cup match against West Ham this Sunday. A team who has a splendid away record this season against a United side slipping further down the slippery slope of failure.
Thanks for reading.