Is obliged to finish late, in a hurry (5)
I believe the answer is:
haste
'in a hurry' is the definition.
(I've seen this before)
'is obliged to finish late' is the wordplay.
'is obliged' becomes 'has'.
'to finish' indicates taking half.
'late' halved is 'te'.
'has'+'te'='HASTE'
(Other definitions for haste that I've seen before include "''Marry in . . . . ., repent at leisure''" , "Over-eager speed" , "go at speed" , "Excessive speed or urgency" , "Overly eager speed" .)