Certify where cricket enthusiasts may be? (6)

I believe the answer is:

attest

'certify' is the definition.
(synonyms)

I don't understand how the rest of the clue works.

(Other definitions for attest that I've seen before include "say, in court" , "Swear to" , "Give evidence - sounds a trial" , "Give sworn evidence" , "Give proof" .)

I've seen this clue in The Times.

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