Sports field - in Red Square naturally (5)
I believe the answer is:
arena
'sports field' is the definition.
'arena' can be an answer for 'field' (synonyms). I'm not sure about the 'sports' bit.
'in red square naturally' is the wordplay.
'in' indicates a hidden word.
'ARENA' can be found hidden inside 'red square naturally'.
Can you help me to learn more?
(Other definitions for arena that I've seen before include "Wembley, for example" , "The place of action" , "domain" , "Ring; stadium" , "Place of combat" .)