AC Milan hero Billy Costacurta has urged coach Stefano Pioli to adjust his defensive tactics.
Milan go into the derby with Inter Milan struggling for form.
Costacurta said: I believe Milan players are accustomed to different systems, but they have to rely on their attitude at the moment.
Tactics can help, but right now defence is the real problem. I think they need to regain defensive solidity to boost their self-confidence.
They created some good chances against Sassuolo and had two goals disallowed for offside. It's not about defence as a department, the problem is the defensive phase and adding one midfielder goes towards this direction."
