Eventually observing the correct rhythm (2,4)
I believe the answer is:
in time
'eventually' is the definition.
(synonyms)
'the correct rhythm' is the wordplay.
'the correct' becomes 'in' (I can't justify this - if you can you should give a lot more credence to this answer).
'rhythm' becomes 'time' (time is a kind of rhythm).
'in'+'time'='IN TIME'
'observing' is the link.
Can you help me to learn more?
(Other definitions for in time that I've seen before include "on schedule" , "Early enough" , "eventually" , "What an orchestra should be" , "not too late" .)