Youth
It is hard to believe that Zouma is just 20-years-old; the former Saint Etienne rock looks far more established for his age, and this is a crucial characteristic that has enabled John Terry and Gary Cahill to be at ease playing alongside him.
The centre-back has years of playing-time ahead of him, and Mourinho should consider the u21 France international a long-term replacement for 34-year-old John Terry.