I reported chasing dog with no lead - what a sight! (5,3)
I believe the answer is:
eagle eye
'what a sight' is the definition.
(I have seen 'Keen sight' mean 'eagle eye' so perhaps 'sight' could also mean 'eagle eye')
'i reported chasing dog with' is the wordplay.
'reported' indicates a 'sounds like' (homophone) clue.
'chasing' means one lot of letters go next to another (some letters chase after others).
'dog with' becomes 'eagle' (I can't explain this - if you can you should give a lot more credence to this answer).
'i' is a homophone of 'eye'.
'eye' put after 'eagle' is 'EAGLE-EYE'.
'no lead' acts as a link.
I am not very happy about this link. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for eagle eye that I've seen before include "Keen sight" , "Ability to observe fine detail" , "one envisages a long way off" , "Critical inspection" , "Keenness of vision" .)