Scorers: Liverpool - Sturridge (69); Manchester United - Mata (14, 59)
Juan Mata scored in each half, either side of Reds captain Steven Gerrard getting sent off just 43 seconds after coming on as a substitute at the interval, and, although Daniel Sturridge pulled a goal back, United could still afford to miss an added-time Wayne Rooney penalty.
The visitors were the dominant force in the first half having got their tactics spot on and Van Gaal said they used Liverpool’s own strengths – their intent to press and attack at speed – against them.
“We beat them again with their own weapons and the pressure on the ball,” he said. “Now the gap is five points ahead of Liverpool and six ahead of Tottenham and Southampton so the win is one of the most important in my career.
“The first half was very good because I knew in advance Liverpool would press us and they did and we played them off the pitch. We scored a fantastic goal and gave nothing away so it was a superb first half.
“I come in the dressing room and I give all my compliments again but then, in the second half, everything changed because of the red card and we did not play like a team any more.
“We were running with the ball, unnecessarily losing the ball and when we didn’t have the ball we didn’t press the opponent with the ball and that was different. The second half we were not so good and that is amazing a little bit because we played 11 against ten and it should be easier but it was not.
“Nevertheless, we didn’t give many chances away because I cannot remember [David] De Gea making a fantastic save.
“He has saved us a lot of times this season but I cannot remember a save.”
Liverpool manager Brendan Rodgers admitted his side’s failure to get going, even before Gerrard’s moment of madness, cost them.
“We were never in position. In the second half, the players showed why we have been on the run with the character and the resilience and we were still in it right to the end.
“They take great credit from that. The first half cost us more than the second.
“In that system you have to be able to press well and pass well and, if you don’t do both elements of the game, it becomes much more difficult for you.
“In the first half we weren’t passing it anything like well enough, We didn’t play well enough, you have to accept that.”
A win would have taken Liverpool above United into the top four for the first time since the opening day of the season but now they have to make up five points in the remaining eight matches.
“It is a big challenge but when I looked at the ten games that were remaining, it was always going to be difficult to win all ten. We built in a loss and some draws,” Rodgers added. “We hoped to win this game against a rival but it is still very much possible. There are five points between us and them.
“We need to recover and use this as a springboard as we did when we last played them [their last league defeat before this encounter]. We are more than capable of winning the next game.”
There was some suggestion Liverpool could have had Martin Skrtel sent off in the final action of the match for a lunge at De Gea but Rodgers rejected that.
“It looks like it when it is slowed down he has caught him with intent. I didn’t see it like that. He is trying to get the ball,” he added.
“You see his foot up. That is a symbol when a player is just trying to get his toe on the ball because if he does that and the keeper brings him down, it is probably a penalty.”
Gerrard’s moment of madness came with a stamp on Ander Herrera. There was almost an audible gasp of disbelief from the majority of the 44,405 inside Anfield when referee Martin Atkinson produced a red card.
For all his frustration at having to watch from the sidelines in a fixture in which he has scored seven times in his last 11 league meetings, it was inexcusable from the most experienced player on the field.
United playing a high midfield four behind lone striker Wayne Rooney meant Mata and Ashley Young were pushed into advanced positions and the former, in particular, used it to great effect against the relatively inexperienced Alberto Moreno.
The Spanish World Cup winner cleverly moved from outside to inside and back again to generate space for himself and the 22-year-old left-back was left in a quandary whether to mark or hand over to centre-back Mamadou Sakho.
Herrera spotted this weakness and in the 14th minute threaded a pass between the two Liverpool players for his compatriot to run on to and clip a shot past goalkeeper Simon Mignolet.
Special guest Pele had met compatriots Philippe Coutinho and Lucas Leiva, back in the squad after a six-week absence, before kick-off to offer some inspiration but whatever he said appeared to have the opposite effect on Coutinho, who over-complicated things.
Phil Jones escaped with a yellow card for clattering Jordan Henderson out by the touchline with a high challenge but that was the least of Liverpool’s problems as Mata finished off a clever reverse pass from substitute Angel di Maria to acrobatically volley home.
Coutinho teed up Sturridge to score his fifth goal of an injury-disrupted season and, although Liverpool made light of their numerical disadvantage, United – with Marouane Fellaini winning virtually every header at both ends of the pitch – had enough discipline and nous to hold on.
They could even afford for Rooney to have a penalty saved by Mignolet in added time after Emre Can’s foul on Daley Blind.
Liverpool: Mignolet, Can, Skrtel, Sakho, Sterling, Henderson, Allen, Moreno (Balotelli 66), Lallana (Gerrard 46), Sturridge, Coutinho. Subs Not Used: Jones, Johnson, Toure, Lambert, Lucas.
Manchester United: De Gea, Valencia, Smalling, Jones, Blind (Rojo 90), Carrick, Mata, Ander Herrera (Falcao 83), Fellaini, Young (Di Maria 55), Rooney. Subs Not Used: Da Silva, Januzaj, Valdes, Pereira.
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