Tear off at pace (4)
I believe the answer is:
rate
'pace' is the definition.
(I know that pace can be written as rate)
'tear off' is the wordplay.
'off' is an anagram indicator.
'tear' anagrammed gives 'RATE'.
'at' acts as a link.
(Other definitions for rate that I've seen before include "Measure of frequency; merit" , "Strongly criticise" , "standard levy" , "Tariff" , "Admire" .)