Season's opening practice has athlete madly keen (9,2,3,5)

I believe the answer is:

straining at the leash

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

'season's opening practice has athlete madly keen' is the definition.
I don't know anything about this answer so I can't tell whether this works.

'season's opening practice has athlete madly' is the wordplay.
'opening' suggests taking the first letters.
'practice' becomes 'training' (I am not sure about this - if you are sure you should believe this answer much more).
'madly' is an anagram indicator.
The first letter of 'seasons' is 's'.
'has'+'athlete'='hasathlete'
'hasathlete' with letters rearranged gives 'attheleash'.
's'+'training'+'attheleash'='STRAINING AT THE LEASH'

Can you help me to learn more?

(Another definition for straining at the leash that I've seen is " Raring to go".)

I've seen this clue in the Sydney Morning Herald.

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.