Group round bar suffering reversal in game (6)
I believe the answer is:
tennis
'game' is the definition.
(tennis is a kind of game)
'group round bar suffering reversal' is the wordplay.
'group' becomes 'set'.
'round' indicates putting letters inside.
'bar' becomes 'inn' (I've seen this in other clues).
'suffering reversal' says the letters should be written backwards.
'set' enclosing 'inn' is 'sinnet'.
'sinnet' written backwards gives 'TENNIS'.
'in' acts as a link.
(Other definitions for tennis that I've seen before include "Medieval, originally French, sport, codified by the British" , "Sent in to play the game, oddly" , "Game played with racquets" , "event" , "Racquet-game" .)