Former AC Milan coach Arrigo Sacchi has weighed into the debate around Theo Hernandez.
The France fullback has lost his first-choice status under coach Stefano Pioli.
Sacchi said, "I always say: you have to use persuasion, and if you don't succeed, percussion. Sometimes leave out those who don't as it should, it can also be good for the person concerned.
"Whoever is intelligent understands, and Pioli knows who a shock can work with... Let us remember that football was born as an offensive team sport: thinking that defending yourself is enough and that the individual solves everything it's a mistake.
"The winning team changes, and how: it's when something works that it needs to be corrected. Can shock therapy with De Ketelaere work? The moment is difficult, I would focus on those players who are able to handle the particular weight of this phase."
