Stake that is added later (4,3)

'is added later' is the definition.
I don't know anything about this answer so I can't judge whether it can be defined by this definition.

'stake' is the wordplay.
I cannot really understand how this works, but
'stake' could be 'bet' (synonyms) and 'bet' is located in the answer.
The remaining letters 'side' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).

'that' acts as a link.

Can you help me to learn more?