Defend like his life depends on it

Obviously.

Luis is there after all to be a left back and defend.

Jose Mourinho might enjoy the width that his full backs can provide but at the end of the day, they are full backs.

Previous occupant of this position, Ashley Cole, could get forward no problem, but adapted his game to make sure that the emphasis was on the defending.

Failing to track back after a run forward is a fast track way to bring dropped.

Azpilicueta may lack slightly going forward, but in terms of defending, he is top draw.

Luis must be as good, if not better.