Call from drinker as he put in blue straws (4,3,5)
I believe the answer is:
down the hatch
'call from drinker' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.
'he put in blue straws' is the wordplay.
'put in' means one lot of letters goes inside another.
'blue' becomes 'down' (I've seen this before).
'straws' becomes 'thatch' (I am not sure about this - if you are sure you should believe this answer much more).
'down'+'thatch'='downthatch'
'he' going within 'downthatch' is 'DOWN THE HATCH'.
'as' is the link.
Can you help me to learn more?
(Other definitions for down the hatch that I've seen before include "(As a toast) drink up!" , "below deck? - with 9a" , "evokes cheers" .)