Pull leader from Sunday Express (6)
I believe the answer is:
strain
'pull' is the definition.
(I've seen this before)
'leader from sunday express' is the wordplay.
I cannot quite see how this works, but
'from' could be 'in' (I've seen this in other clues) and 'in' is found in the answer.
'sunday' could be 's' and 's' is present in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for strain that I've seen before include "Drain off" , "variety" , "Distinct breed (of animal); overexert" , "Pass through a sieve" , "Put through a perforated device to separate" .)