The hosts made the breakthrough in the first half when Daniel Sturridge beat David De Gea from the penalty spot after Nathaniel Clyne was brought down by Memphis Depay.
There was a lack of fight, urgency and cohesion in the team
Liverpool midfielders Adam Lallana and Philippe Coutinho wasted great opportunities to double the home side’s lead before half-time.
However, Roberto Firmino handed the Reds a commanding 2-0 first-leg lead at Anfield after a close-range finish with 17 minutes remaining of the first leg.
Former United defender Ferdinand warned Louis van Gaal’s side that there would need to be a massive, massive improvement ahead of the return leg next Thursday night.
“Sitting up here watching this surrounded by Liverpool fans, it isn’t easy speaking as someone who became a Man Utd fan after playing there for many years,” Ferdinand told BT Sport.
“There was a lack of fight, urgency and cohesion in the team. There will have to be a massive, massive improvement in the next leg because that wasn’t good enough. There are no excuses.”
Liverpool’s 2-0 win was their first victory over their bitter rivals United in four attempts.
Van Gaal’s host West Ham United in the FA Cup quarter-final at Old Trafford on Sunday afternoon before Liverpool travel to Manchester for the return leg.
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