Register a player in the French clubs (7)
I believe the answer is:
almanac
'register' is the definition.
(I've seen this before)
'a player in the french clubs' is the wordplay.
'player' becomes 'man'.
'in' is an insertion indicator.
'the french' becomes 'la' (one of the French words for 'the').
'clubs' becomes 'c' (abbreviation in card games).
'man' going within 'la' is 'lmana'.
'a'+'lmana'+'c'='ALMANAC'
(Other definitions for almanac that I've seen before include "Statistical annual" , "issue every year" , "Informative calendar" , "Annual publication containing information in a particular field" , "Calendar with astronomical data and other information" .)