Club welcoming rogue at first, ill-mannered child (4)
I believe the answer is:
brat
'ill-mannered child' is the definition.
(I've seen this before)
'club welcoming rogue at first' is the wordplay.
'club' becomes 'bat' (bat is a kind of club).
'welcoming' means one lot of letters goes inside another (in sense of 'inviting in').
'at first' indicates taking the first letters.
The initial letter of 'rogue' is 'r'.
'bat' enclosing 'r' is 'BRAT'.
(Other definitions for brat that I've seen before include "Irritating youngster" , "Nasty little kid" , "Nasty child" , "Young rascal" , "Urchin" .)