Crossword Genius

Rodent performing in shop (3,2)

Ross

I believe the answer is:

rat on

'shop' is the definition.
(both can mean to betray or inform upon)

'rodent performing' is the wordplay.
'rodent' becomes 'rat' (rat is a kind of rodent).
'performing' becomes 'on' (as in being on stage).
'rat'+'on'='RAT ON'

'in' acts as a link.

(Other definitions for rat on that I've seen before include "Betray" , "shop" , "Give away" , "desert" , "grass up" .)

I've seen this clue in The Times.
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