Very strong, all the players with club (4-4)
I believe the answer is:
cast-iron
'very strong' is the definition.
(I've seen this before)
'all the players with club' is the wordplay.
'all the players' becomes 'cast' (group of actors).
'with' means one lot of letters go next to another.
'club' becomes 'iron' (type of golf club).
'cast'+'iron'='CAST-IRON'
(Other definitions for cast-iron that I've seen before include "Extremely robust" , "Very strong" , "Rigid, unyielding" , "Unassailable" , "Unbreakable" .)