Sport left burden in AE (8)
I believe the answer is:
lacrosse
'sport' is the definition.
(I know that lacrosse is a type of ball game.)
'left burden in ae' is the wordplay.
'left' becomes 'L' (common abbreviation).
'burden' becomes 'cross' (someone's particular burden is their cross).
'in' means one lot of letters goes inside another.
'cross' placed inside 'ae' is 'acrosse'.
'l'+'acrosse'='LACROSSE'
(Other definitions for lacrosse that I've seen before include "Like thirteen of the other clues in the French" , "Score's uncertain after the Spanish" , "Game played with a netted stick" , "Sport played with sticks" , "Ball game using netted stick" .)