Game in which you go astray, then catch up (6)
I believe the answer is:
tennis
'game in which you' is the definition.
'tennis' can be an answer for 'game' (tennis is a kind of game). I am not certain of the remainder of the definition.
'go astray then catch up' is the wordplay.
'go astray' becomes 'sin' (I've seen this before).
'then' is a charade indicator (letters next to each other).
'catch' becomes 'net' (netting is a kind of catching).
'up' says the letters should be written backwards (in down clue: letters go upwards).
'sin'+'net'='sinnet'
'sinnet' backwards is 'TENNIS'.
Can you help me to learn more?
(Other definitions for tennis that I've seen before include "- elbow; - shoe" , "Sport Dwight Davis gave trophy for" , "Sent in to play the game, oddly" , "Sent in strangely to play the game" , "Game of the Williams sisters and of Roger Federer" .)