The Reds were taking part in the last game of their pre-season tour of America against Sporting at Yankee Stadium on Wednesday night, and got off to the worst start possible.
After just four minutes, Manchester United transfer target Bruno Fernandes picked up the ball halfway through the Liverpool half, before looping a shot at Mignolet.
His effort was relatively weak, and aimed straight at the Belgian goalkeeper.
However, the Liverpool back-up stopper fumbled the ball into his own net, allowing the ball to bounce off his hands into the goal.
Reds fans were enraged by the horror mistake, and begged the club to allow him to leave.
“Buy Fernandes sell Mignolet,” one wrote.
Another tweeted: “Sell mignolet sick of it.”
One upset fan tweeted: “Time comes when you have to move on! Great lad that he is. It’s only for his sake.”
“This guy is actually so bad,” one wrote.
“Can we just sell him now, I am tired of this,” tweeted another fan.
One posted: “This is why he is on the bench …..calamity magnet”
Another wrote: “He won’t play one single EPL game. He is aware of that.”
Despite fans being upset with Mignolet, the club apparently has no interest in letting him go this summer.
Earlier this month it was confirmed by Klopp that he expects the goalkeeper to remain at Anfield next season to provide cover for Alisson Becker.
Liverpool managed to get themselves back in the game at Yankee Stadium, with goals from Divock Origi and Georginio Wijnaldum giving them a 2-1 lead at half-time.
