Isak was injured in the act of scoring Liverpool's opening goal against Tottenham on Saturday, with Van de Ven wrapping his legs around the striker’s left leg.
The Swedish international has since had surgery as he prepares for 3 months on the sidelines. Manager Arne Slot said the tackle was “reckless” and that Isak was unlucky to be in such a position after the game as he deals with the loss of the £125M star.
Speaking in his latest press conference, Frank says he disagrees with Slot’s comments and backed Van de Ven’s actions.
“Obviously I am disagreeing.
"In many ways, we are talking about a defender that will do everything to avoid (conceding) the goal. It’s a transition so he is sprinting back in. There’s a ball slid down in the side, and he does everything he can to block that shot.
"Unfortunately, Isak has planted his foot straight there, which makes it look worse than it is. That would be a natural reaction for any defender.
"Or, put it this way, if my defender doesn’t do that, I don’t think they are true defenders. I don’t see that at all. I think reckless challenges, normally, you haven’t seen any from Micky, as I remember it. I see him as a very fair and competitive player. That’s one thing. I also know the two players have sorted it out so that’s a good sign."
Bournemouth winger Antoine Semenyo has been heavily linked with a move to Anfield, and reports suggest that the 25-year-old could step into to replace Isak next month.