Starting professional tournament ranking, say (10)

I believe the answer is:

proceeding

I'm a little stuck... Click here to teach me more about this clue!

'starting' is the definition.
The definition and answer can be both acts as well as being singular nouns.
Perhaps they are linked in a way I don't understand?

'professional tournament ranking say' is the wordplay.
'professional' becomes 'pro' (abbreviation).
'tournament ranking' becomes 'seeding' (eg for tennis).
'say' shows a homophone (sound like).
'seeding' sounds like 'ceeding'.
'pro'+'ceeding'='PROCEEDING'

Can you help me to learn more?

(Another definition for proceeding that I've seen is " going ahead".)

I've seen this clue in the Sydney Morning Herald.

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