You don't need to be a top player, but a good amount of playing experience at (close to) a top level will sure help when things get heated up. If not you better also have the same amount of rock solid personal confidence Jose Murinho has.
Thank you for the response ..and yes Jose Mourniho has a rock solid confidence but his progress was greatly influenced by the fact that his father Felix Mourniho was the goal keeper for Portugal.That must have made the start for him relatively much easier.Infact i've read his biography by Patrick Barclay "Anatomy of a Winner" and this point seems quite evident since he got most of the initial training in coaching while working under his father.And also dont forget the guy was born with a silver spoon.And i think that when you combine these two factors , it can really bolster one's progress.
I instead regard Arsene Wenger as someone to really look upto because from whatever i've read about his career , it appears that the man started from the scratch and worked his way up.