Dejan Lovren has accused a Liverpool fan page of being "full of shit" after they criticised goalkeeper Loris Karius.
Karius made two high-profile errors as Liverpool lost the Champions League final in May, while his form so far in pre-season has also been questionable with mistakes against Tranmere Rovers and Borussia Dortmund.
Concerns over the position led to the Reds spending a world-record fee to bring Alisson Becker to the club, leaving Karius facing the prospect of either leaving Anfield or acting as the Brazilian's backup.
A Liverpool fan page on Instagram uploaded a video of Karius's mistake against Dortmund along with the captain: "Thank god we've got Alisson. It's becoming a regular thing for Karius. I seriously believe that we should sell him because even as a backup he's just full of mistakes.
"I don't care what anyone says but he is not worthy of wearing the Liverpool shirt. And this is for all the mistakes he makes in general for the ones thinking that I'm slaughtering him just for this."
However, Lovren took exception to the criticism and responded: "You are full of shit. Shame on you how you treat our player! And also the name Liverpool fan page."
Karius has featured in all of Liverpool's pre-season games so far, with Alisson still enjoying an extended break after the World Cup.