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 wordplay.
'stalwart' becomes 'brick' (I've seen this in other clues).
'that goes to' says to put letters next to each other.
'club' becomes 'bat' (bat is a kind of club).
'from' acts as a link.
(Other definitions for brickbat that I've seen before include "Criticism", "Highly critical remark", "(Critic's) weapon", "Piece of blunt criticism", "Critical remark", "Building block used as missile", "Hostile criticism - missile", "An uncomplimentary remark, or kind of missile", "Missile, criticism" and "Strong criticism".)