Open: Lord's venue for playing (10)
I believe the answer is:
unresolved
'open' is the definition.
(I know that open can be written as unresolved)
'lord's venue for playing' is the wordplay.
'for playing' is an anagram indicator.
'lords'+'venue'='lordsvenue'
'lordsvenue' is an anagram of 'UNRESOLVED'.
(Other definitions for unresolved that I've seen before include "Not finally settled" , "up in the air" , "(to be continued)" .)