Make a shocking debut at short leg (7)

I believe the answer is:

startle

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

'make a shocking debut' is the definition.
The answer and definition can be both acts as well as being singular nouns.
Maybe there's a link between them I don't understand?

'at short leg' is the wordplay.
'at' becomes 'start' (I can't explain this - if you can you should believe this answer much more).
'short' means to remove the last letter.
'leg' with its last letter removed is 'le'.
'start'+'le'='STARTLE'

Can you help me to learn more?

(Other definitions for startle that I've seen before include "Rattles (anag.)" , "Frighten suddenly" , "Shock (someone)" , "Take by surprise" , "Alarm suddenly" .)

I've seen this clue in the Evening Standard.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.