Jose Mourinho has done the unthinkable and returned to Chelsea for a second spell in the hot seat.
It is a well known fact in football that you shouldn't return to clubs you have experienced success with in the past, as it will always be difficult to replicate it.
After a shaky start to the season, Mourinho faces a tough task in transforming his team's fortunes.
Will the "special one" live to regret his return to London?
GMS contributor Matthew Wall takes a look at 5 managers before him that have had contrasting success when returning for a second spell at their clubs.
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