Survived the heat, presumably weakened (9)
I believe the answer is:
qualified
I believe this is a double definition.
'survived the heat presumably' is the first definition.
(as in qualifying for a competition in a heat)
'weakened' is the second definition.
(qualify can mean to weaken or make conditional)
(Other definitions for qualified that I've seen before include "guarded" , "Provided with the attributes necessary to do a job" , "Having credentials" , "Professional" , "Passed exams - with reservations" .)