Run fantastic 400m, perhaps (4)

I believe the answer is:

race

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

'400m perhaps' is the definition.
I can't judge whether this definition defines the answer.

'run fantastic' is the wordplay.
'run' becomes 'r' (cricket abbreviation).
'fantastic' becomes 'ace' (ace can informally mean very good).
'r'+'ace'='RACE'

Can you help me to learn more?

(Other definitions for race that I've seen before include "See 22" , "People; dash" , "See 23" , "People - sprint - competition" , "Run, dash" .)

I've seen this clue in The Times.

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