Seeing is believing, or so we were told.
Yet, even with the benefit of technology - endless replays, all the angles, freeze frames - we still cannot believe what we are seeing.
It was yet another matchday where what VAR failed to spot - Harry Maguire’s headlock on Cesar Azpilicueta in Manchester United’s goalless draw with Chelsea - to what it did: a penalty when Fabinho tried to thieve the ball off Oliver McBurnie, didn’t compute.
Fabinho, stationed next to Joe Gomez at centre-back again in the absence of Virgil van Dijk, slid in on the edge of the box to thwart McBurnie in possession.
He won the ball and struck some of the forward’s foot with referee Mike Dean believing it to be a foul. Marriner reviewed the incident, but only checked if it was inside or outside the area, making no judgement on the contact itself.
Dean pointed to the spot, Sander Berge sent the returning Alisson the wrong way and United were 1-0 up with Liverpool completely losing all direction until the final five minutes of the half.
Chris Wilder’s men were excellent after their opener, which erased the unwanted record of being the only side yet to take the lead in a Premier League clash this season.
They were supremely compact without the ball, while George Baldock, McBurnie and Berge in particular caused problems for the hosts. They were aerially dominant, more energetic, stronger in the duels and profiting off second balls. Rhian Brewster, earning his first start against his former club, worked as tirelessly as his team-mates.
Liverpool, meanwhile, were unable to create anything; their tempo so pedestrian and play so predictable.
They were fortunate that VAR had another moment of eyesight failure, missing Diogo Jota’s trip on Berge inside the area that qualified as a clear penalty.
Short minutes later at the other end, Roberto Firmino tapped in after goalkeeper Aaron Ramsdale could only parry a close-range Sadio Mane header.
After the hour-mark, Mohamed Salah’s superb two-touch finish was correctly chalked off as he was offside when darting to meet Trent Alexander-Arnold’s delivery.
Right afterwards, United’s new deficiency of not stopping crosses was punished as Mane’s lifted ball to the far post from the left was met with a Jota header to give Liverpool the lead.
It also served as the winner against a team that hadn't scored more than once in any of their last 13 away games in the top-flight.
Substitute David McGoldrick was introduced and immediately pounced on a loose Fabinho header, but his half-volley went wide.
Salah hit the post late on after showing stellar strength and feet and Liverpool extended their unbeaten league streak at Anfield to 62 games, winning 28 of their last 29 here.
But the conversation will once again be dominated by what VAR did and didn’t spot. Seeing is meant to be believing, after all.
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