Intimidate to restrict runs and hinder opener
I believe the answer is:
crowbar
'opener' is the definition.
(I have seen 'Powerful opener' mean 'crowbar' so perhaps 'opener' could also mean 'crowbar')
'intimidate to restrict runs and hinder' is the wordplay.
'intimidate' becomes 'cow' (I've seen this before).
'to restrict' means one lot of letters goes inside another.
'runs' becomes 'r' (cricket abbreviation).
'and' means one lot of letters go next to another.
'hinder' becomes 'bar' (I can't explain this - if you can you should give a lot more credence to this answer).
'cow' going around 'r' is 'crow'.
'crow'+'bar'='CROWBAR'
Can you help me to learn more?
(Other definitions for crowbar that I've seen before include "Powerful opener" , "Burglar's tool, perhaps" , "Jemmy" , "Tool for breaking and entering" , "Iron lever for prising" .)