Regretting game in capital of Ghana (5)
I believe the answer is:
ruing
'regretting' is the definition.
('rue' can be a synonym of 'regret')
'game in capital of ghana' is the wordplay.
'game' becomes 'ru' (rugby union).
'capital of' says to take the initial letters.
The first letter of 'ghana' is 'g'.
'ru'+'in'+'g'='RUING'
(Other definitions for ruing that I've seen before include "Feeling sorry for" , "Having second thoughts" , "Bitterly regretting" , "full of remorse?" , "Regretful" .)