Immediately placed in an awkward situation (2,3,4)
I believe the answer is:
on the spot
'immediately' is the definition.
(I've seen this before)
'placed in an awkward situation' is the wordplay.
'placed' becomes 'th' (I can't explain this - if you can you should give a lot more credence to this answer).
'in' indicates putting letters inside.
'an' becomes 'one'.
'awkward situation' becomes 'spot' (I've seen this before).
'th' placed within 'one' is 'onthe'.
'onthe'+'spot'='ON-THE-SPOT'
Can you help me to learn more?
(Other definitions for on the spot that I've seen before include "Colour is replaced here" , "replacing ball from pocket here?" , "Where snooker ball may be replaced" , "Under pressure" , "Live" .)