The space behind the full-back 🧐

In Milan's 3-1 win at Como, the first ten minutes confirmed what the shape suggested. Como pushed Van de Bremt high on the left, and Milan's back three never adjusted. That left a clear lane between Bartesaghi and the left centre-back. Como's opener came from exactly that side.

After the break, Allegri moved Leao back to a true left-wing role. Suddenly Van de Bremt had to think about tracking a runner, not just attacking. The space behind him disappeared. Rabiot attacked that channel twice, once winning the penalty and later scoring.

One positional change removed an entire passing lane from Como's build-up.

Question: When a full-back pushes high, who is responsible for covering the space behind him in your team's shape?