Call for round gets you tense inside bar (4,3)
I believe the answer is:
shut out
'bar' is the definition.
(thesaurus)
'call for round gets you tense' is the wordplay.
'call for round' becomes 'shout' (I can't explain this - if you can you should believe this answer much more).
'gets' indicates putting letters inside (gets can mean captures or absorbs).
'you' becomes 'u' (I've seen this in other clues).
'tense' becomes 't' (abbreviation used in many dictionaries).
'u'+'t'='ut'
'shout' placed around 'ut' is 'SHUT-OUT'.
'inside' is the link.
Can you help me to learn more?
(Another definition for shut out that I've seen is " Excluded".)