Regarded as having referred to introducing a wine (8)
I believe the answer is:
credited
'regarded as' is the definition.
The answer and definition can be both related to thinking as well as being past participle verbs.
Maybe there's an association between them I don't understand?
'referred to introducing a wine' is the wordplay.
'referred to' becomes 'cited' ('cite' can be a synonym of 'refer to').
'introducing' is an insertion indicator (some letters introduced or inserted into others).
'a wine' becomes 'red' (red wine is an example).
'cited' enclosing 'red' is 'CREDITED'.
'having' is the link.
Can you help me to learn more?
(Other definitions for credited that I've seen before include "Believed" , "Acknowledged as writer" , "Esteemed" , "3 across (anag.)" , "given improved balance" .)