Manchester City picked up a 4-1 win in their latest pre-season friendly versus Championship side Blackpool on Tuesday.
Goals from Samuel Edozie, Riyad Mahrez and Ilkay Gundogan (x2) sealed victory for the Premier League champions at the Etihad Stadium.
While City eventually won the game by three clear goals, Blackpool certainly gave it a good go and the scores were actually level at 1-1 for 27 minutes of play.
Former Everton left-back Luke Garbutt was the man who equalised for the team from England's second-tier and he did so from the penalty spot in the 21st-minute.
City's Ruben Dias was the man responsible for giving away the spot kick.
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The Portugal international was left chasing shadows on the edge of his own penalty area by Shayne Lavery, with Dias eventually tripping the Blackpool striker inside the area.
It was a moment to forget for the 2020/21 Premier League Player of the Season and his failure to stop Lavery has unsurprisingly resulted in a savage reaction from Liverpool fans on social media.
Last week, Virgil van Dijk was ridiculed for making a mistake on his return to action versus Hertha Berlin, so supporters are getting their revenge.
Let's take a look at Dias' error...
Dias vs Lavery
Fan reaction
Liverpool fans were never going to let a Dias mistake slide, were they?
The former Benfica man enjoyed an incredible debut season at City in 2020/21 and was labelled by many as the main reason why the team triumphed in the Premier League.
However, Dias was unable to replicate his stellar domestic form at Euro 2020 with Portugal and he was subjected to criticism as a result.
But despite his poor showings this summer on international duty, there's no doubting that the 24-year-old is a world-class operator and a mistake versus Blackpool doesn't change that either.
Dias might not be at Van Dijk's level just yet, but he's not far off.