Pacific nation’s new sport bagging gold (5)
I believe the answer is:
nauru
'pacific nation's' is the definition.
(country in the Pacific Ocean)
'new sport bagging gold' is the wordplay.
'new' becomes 'n' (common abbreviation eg NT for New Testament).
'sport' becomes 'RU' (rugby union).
'bagging' means one lot of letters goes inside another (bag can mean to take or obtain).
'gold' becomes 'Au' (Au is the chemical symbol for gold).
'n'+'ru'='nru'
'nru' going around 'au' is 'NAURU'.
(Other definitions for nauru that I've seen before include "SW Pacific republic" , "Pacific coral island republic, once rich in phosphates" , "little nation" , "Pacific republic, formerly Pleasant Island" , "Fairground carousel" .)