Rising Oregon tenor's opening line for skilled musician (7)
I believe the answer is:
maestro
'skilled musician' is the definition.
(maestro can mean a distinguished musician)
'rising oregon tenor's opening line' is the wordplay.
'rising' says the letters should be written in reverse (going up in a down clue).
'oregon' becomes 'or'.
'opening' suggests taking the first letters.
'line' becomes 'seam' (synonyms).
The initial letter of 'tenors' is 't'.
'or'+'t'+'seam'='ortseam'
'ortseam' back-to-front is 'MAESTRO'.
'for' is the link.
(Other definitions for maestro that I've seen before include "ace" , "Highly skilled musician" , "Good conductor" , "Expert in music etc" , "Virtuoso" .)