Worker left half abandoned gets to manage (6)
'manage' is the definition.
'worker left half abandoned' is the wordplay.
'worker' becomes 'hand' (hand is a kind of worker).
'left half' means to take half the letters.
'abandoned' becomes 'left' (I've seen this before).
'left' halved is 'le'.
'gets to' acts as a link.
(Other definitions for handle that I've seen before include "Manage or deal with - in manual way?", "Treat", "Deal with - one's name (slang)", "Deal with; name (colloq.)", "Ability to walk on board ship".)