Money, after reflecting, no object after cardplayers have a rethink (6,4,4)
I believe the answer is:
change ones mind
'have a rethink' is the definition.
(I've seen this before)
'money after reflecting no object after cardplayers' is the wordplay.
I cannot really see how this works, but
'money' could be 'change' (I've seen this before) and 'change' is present in the answer.
'no' could be 'o' (resembles 0 - 'no' can mean 'zero') and 'o' is located in the answer.
'object' could be 'sm' (Sm is an example) and 'sm' is found in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for change ones mind that I've seen before include "Rethink things" , "Have buyer's remorse, say" .)