Come to grief when autumn's ended (4,4)

I believe the answer is:

fall over

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

'come to grief' is the definition.
I can't judge whether this definition defines the answer.

'autumn's ended' is the wordplay.
'autumn' becomes 'fall' (synonyms).
'ended' becomes 'over' (synonyms).
'fall'+'over'='FALL OVER'

'when' is the link.

Can you help me to learn more?

(Other definitions for fall over that I've seen before include "collapse" , "Trip" , "Take a tumble" .)

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.