Conversation so far:
What is napoli?
Società Sportiva Calcio Napoli, commonly referred to as Napoli, is an Italian professional football club based in Naples, Campania that plays in Serie A, the top flight of Italian football.
What happened at the peak of Diego Maradona's career?
inherited the captain's armband from Napoli veteran defender Giuseppe Bruscolotti and quickly became an adored star among the club's fans.

Question: How was he as a coach?
Self-contained rewrite: How was Diego Maradona as a coach?