Aware that what you're tackling is linked to racket (5,2)

'aware that' is the definition.
I can't judge whether this defines the answer.

'you're tackling is linked to racket' is the wordplay.
'you're tackling' becomes 'clue' (I can't justify this - if you can you should give a lot more credence to this answer).
'is linked to' means one lot of letters go next to another.
'racket' becomes 'din' (both can mean a loud noise or disturbance).
'clue'+'din'='CLUED-IN'

'what' is the link.

Can you help me to learn more?