The three goals confirmed the visitors’ superiority on an unhappy afternoon when there was no shortage of effort by the Reds, but a lack of cutting edge in the final third.
Nemanja Vidic was sent off for the fourth time against Liverpool after bringing down Daniel Sturridge in the box with 15 minutes left, but Gerrard missed the chance to complete his hat-trick when his penalty hit the post.
Defeat all but ends United’s faint hopes of securing Champions League football for next season and David Moyes’ men must quickly switch focus to this season’s European campaign, and the task of overturning a two-goal deficit to Olympiacos on Wednesday.
Liverpool settled quickly in this match and sprayed the ball around with confidence. Sturridge and Joe Allen missed presentable chances before their opener, which came 12 minutes before the break.
Rafael handled inside the box, referee Mark Clattenburg pointed to the spot and Gerrard sent De Gea the wrong way to put the visitors ahead. Away goalkeeper Simon Mignolet was only tested once in the first half, keeping out Wayne Rooney’s snap-shot not long after Gerrard’s goal.
Any plans put in place at the interval were soon undone when Phil Jones barged in to Allen and, again, Clattenburg decisively awarded a penalty. De Gea guessed right this time but was beaten low to his left by Gerrard.