Urge horse to take disabled one around (3,2)

I believe the answer is:

egg on

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

I cannot understand how the rest of the clue works.

(Other definitions for egg on that I've seen before include "Prompt" , "Fire" , "this face is obvious embarrassment" , "Encourage to act" , "Press" .)

I've seen this clue in The Hindu.

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