Say nothing when on the mat; just show indifference (5)
I believe the answer is:
shrug
'show indifference' is the definition.
(I've seen this before)
'say nothing when on the mat' is the wordplay.
'say nothing' becomes 'sh' (I've seen this in other clues).
'when on' says to put letters next to each other.
'the mat' becomes 'rug' (I've seen this before).
'sh'+'rug'='SHRUG'
'just' is the link.
I am not very happy about this link. It may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for shrug that I've seen before include "display nonchalance" , "Shoulder gesture" , "Sign of indifference" , "Gesture of indifference or ignorance" , "Express silent doubt" .)