Cricketer has to secure tons in derbies (6,4)

I believe the answer is:

bowler hats

'derbies' is the definition.
('bowler hat' can be a synonym of 'derby')

'cricketer has to secure tons' is the wordplay.
'cricketer' becomes 'bowler' (bowler is a kind of cricketer**).
'to secure' indicates putting letters inside.
'tons' becomes 't'.
'has' enclosing 't' is 'hats'.
'bowler'+'hats'='BOWLER HATS'

'in' acts as a link.

I've seen this clue in The Telegraph.

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