Run out of allotment for a drink (6)
I believe the answer is:
potion
'a drink' is the definition.
(potion is a kind of drink)
'run out of allotment' is the wordplay.
'run' becomes 'r' (cricket abbreviation).
'out of' is a deletion indicator.
'allotment' becomes 'portion' (portion is a kind of allotment).
'portion' with 'r' taken out is 'POTION'.
'for' is the link.
(Other definitions for potion that I've seen before include "Drink, maybe philtre" , "Concoction - elixir" , "Magical liquid" , "Drink, maybe medicinal" , "Healing drink" .)