Arrive without a ticket and go down after those attending (9)
I believe the answer is:
gatecrash
'arrive without a ticket' is the definition.
I can't judge whether this definition defines the answer.
'go down after those attending' is the wordplay.
'go down' becomes 'crash' (crashing is a kind of going down).
'after' says to put letters next to each other.
'those attending' becomes 'gate' (the number of people attending a sporting event).
'crash' put after 'gate' is 'GATECRASH'.
'and' is the link.
Can you help me to learn more?
(Other definitions for gatecrash that I've seen before include "join party unofficially" , "join party if not wanted" , "to do so uninvited" , "Try to get in for free" , "enter without invitation" .)