WARNING: This page is about a different car, the 2003 Mazda Protege5, 2003 Mazda Protege, 2002 Mazda Protege5, and 2002 Mazda Protege. However, it is still accessible from the selected car via links, so may be relevant.
Hold the piston down with a cloth-wrapped pin punch.
Fig 1: Holding Piston With Cloth-Wrapped Pin Punch