A turn confused a friend as expected (9)
I believe the answer is:
naturally
'as expected' is the definition.
(thesaurus)
'a turn confused a friend' is the wordplay.
'confused' indicates an anagram.
'a friend' becomes 'ally' (an ally is a friend or supporter).
'a'+'turn'='aturn'
'aturn' with letters rearranged gives 'natur'.
'natur'+'ally'='NATURALLY'
(Other definitions for naturally that I've seen before include "as you might expect" , "In an artless way" , "Without artificial help" , "it goes without saying" , "as anticipated" .)