Liverpool have not lost a league game for 381 days, have lost only one top-flight match in the last 623 days, are unbeaten at Anfield since April 2017 and undefeated in 39 league matches.
A 19th title, which would put them within one of United, is seemingly within their grasp and could be achieved in record time, especially as they have a match in hand over their rivals.
The visitors were not given much chance before kick-off and the confirmation of the absence of top scorer Marcus Rashford, who is likely to be sidelined for a significant period with a reported stress fracture in his back, only increased the odds against them.
Without his pace up front it left them somewhat toothless. In fact, United were everything the league leaders were not: slow to react, ponderous in possession, and lacking in ideas and quality.
Liverpool waited for their opponents’ early energy to subside and then struck after 14 minutes.
The diminutive Brandon Williams was tasked with marking the considerably taller Virgil van Dijk, pictured, from Trent Alexander-Arnold’s corner and the defender did not get off the ground as the Holland international outjumped United’s new captain Harry Maguire to power a header past a static David De Gea.
Roberto Firmino then curled a shot across De Gea and inside the far post but his goal was chalked off by VAR for a foul, which was open to debate, by Van Dijk on the goalkeeper in the build-up.
Georginio Wijnaldum then tucked a shot inside the same post, from Alex Oxlade-Chamberlain’s precise through ball, but was flagged offside and VAR agreed.
As the half drew to a close Sadio Mane forced De Gea into saving with an outstretched foot on the counter-attack, seconds after Andreas Pereira had missed United’s best chance. The Brazilian slid in at the far post but could not get the contact needed on Aaron Wan-Bissaka’s cross.
Liverpool tried to kill off the game in the first ten minutes of the second half, registering seven shots on target, with Salah bundling a shot wide from six yards and De Gea tipping Jordan Henderson’s shot on to the post the best efforts.
When United did get chances they wasted them: Fred shot wide after being gifted the ball from an Alexander-Arnold throw-in while Anthony Martial wildly sliced over having found space down the left.
Liverpool sealed the win in added time when Alisson Becker’s quick punt downfield picked out Mo Salah on his own and he held off Daniel James to slot under De Gea. The Egyptian’s celebration, whipping off his shirt, was uncharacteristic and resulted in an inevitable yellow card.