Tossed last of melon into punch (5)

'tossed' is the definition.
The answer and definition can be both to do with contact as well as being past participle verbs.
Perhaps you can see an association between them that I can't see?

'last of melon into punch' is the wordplay.
'last of' indicates one should take the final letters.
'into' means one lot of letters goes inside another.
'punch' becomes 'slug' (I can't explain this - if you can you should give a lot more credence to this answer).
The final letter of 'melon' is 'n'.
'n' put into 'slug' is 'SLUNG'.

Can you help me to learn more?