Entire first half of Manchester side against Real's awful (9)
I believe the answer is:
universal
'entire' is the definition.
(thesaurus)
'manchester side against real's awful' is the wordplay.
'manchester side' becomes 'uni' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'against' becomes 'v' (abbreviation for 'versus').
'awful' indicates anagramming the letters.
'reals' with letters rearranged gives 'ersal'.
'uni'+'v'+'ersal'='UNIVERSAL'
'first half of' acts as a link.
This may not be right. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for universal that I've seen before include "Of worldwide scope" , "Everywhere applicable" , "Without exception" , "for general viewing" , "Found everywhere" .)