Blunt criticism from stalwart that goes to club (8)
I believe the answer is:
Here is my best explanation:
'blunt criticism' is the definition.
(I've seen this before)
'stalwart that goes to club' is the subsidiary indication.
'stalwart' becomes 'brick' (I've seen this in other clues).
'that goes to' is a charade indicator (letters next to each other).
'club' becomes 'bat' (bat is a kind of club).
'from' is the link.
(Other definitions for brickbat that I've seen before include "Critical remark", "Highly critical remark", "Piece of blunt criticism", "(Critic's) weapon", "Building block used as missile", "Hostile criticism - missile", "An uncomplimentary remark, or kind of missile", "Missile, criticism" and "Blunt criticism".)