After a lively but less than creative start from both teams, it was Villa who opened the scoring in the 21st minute when Trezeguet grabbed his first Premier League goal, volleying in from six yards out after a good free-kick from John McGinn.
The Video Assistant Referee did check whether the Egypt international had strayed offside but after a lengthy look at the incident, the goal was awarded to send Villa Park into hysterics.
Liverpool almost responded immediately when Roberto Firmino tucked home Sadio Mane’s cross from close range, but VAR was once again called into action after the linesman has raised his flag and the goal was eventually ruled out for offside.
The Reds struggled to mount any more clear-cut chances before the break but there was a poor dive from Mane in the box, who was booked after theatrically throwing himself to the ground after a coming together with Frederic Guilbert.
Jurgen Klopp’s men dominated possession after the break but they were uncharacteristically toothless in the final, with 20-yard strikes from Georginio Wijnaldum and Mane the closest they came to an equaliser.
However, in the 87th minute, Mane played a lovely ball towards the back post for the on-rushing Andrew Robertson, who powered a header past Tom Heaton to level the scores.
More drama was to come when in the fourth minute of added time, Trent Alexander-Arnold’s near-post corner was headed into the far corner superbly by Mane, who nipped in between Jonathan Kodjia and Bjorn Engels.
That win keeps Liverpool six points clear at the top of the Premier League and extends their unbeaten run in the top flight to 28 matches.