Charm found during tenth rally (7)
I believe the answer is:
enthral
'charm' is the definition.
(enthral can mean to charm or captivate)
'found during tenth rally' is the wordplay.
'found' indicates the answer is hidden within the clue.
'ENTHRAL' is hidden within 'during tenth rally'.
(Other definitions for enthral that I've seen before include "rivet" , "yoke" , "be captivating?" , "Captivate" , "Beguile" .)