Rugby player worried around a German breed (9)
I believe the answer is:
propagate
'breed' is the definition.
(thesaurus)
'rugby player worried around a german' is the wordplay.
'rugby player' becomes 'prop' (I've seen this in other clues).
'worried' becomes 'ate' (something worrying may eat someone up).
'around' indicates putting letters inside.
'a german' becomes 'ga' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'ate' placed around 'ga' is 'agate'.
'prop'+'agate'='PROPAGATE'
Can you help me to learn more?
(Other definitions for propagate that I've seen before include "Breed from parent stock" , "Disseminate" , "Advertise widely" , "Publicise" , "broadcast" .)