Crossword Genius

Left field of substandard runners hitting this? (3-3-4)

Ross

I believe the answer is:

off-the-wall

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

'left field' is the definition.
(I've seen this before)

'substandard runners hitting this?' is the wordplay.
I cannot quite see how this works, but
'substandard' could be 'off' (I've seen this in other clues) and 'off' is present in the answer.
This may be the basis of the clue (or it may be nonsense).

'of' is the link.

Can you help me to learn more?

(Other definitions for off-the-wall that I've seen before include "like a newly escaped convict?" , "Original" , "Conspicuously or grossly unconventional" .)

I've seen this clue in The Independent.
Want a hint initially instead of a full solution? Install my app