Drag disheartened engineer to game in London (5,6)
I believe the answer is:
tower bridge
'london' is the definition.
I don't know anything about this answer so I cannot judge whether this works.
'drag disheartened engineer to game in' is the wordplay.
'drag' becomes 'tow' (towing is a kind of dragging).
'disheartened' suggests removing the centre (the middle or heart is removed).
'to game in' becomes 'bridge' (I can't explain this - if you can you should give a lot more credence to this answer).
'engineer' with its centre removed is 'er'.
'tow'+'er'+'bridge'='TOWER BRIDGE'
Can you help me to learn more?
(Other definitions for tower bridge that I've seen before include "sight in the capital" , "river crossing" , "a fixture between two Thames boroughs" , "London landmark" .)