A roller cage (1) is provided with a prismatic base body for guiding a minimum of one work roller designed for deep rolling of grooves on crankshaft journals or crank pins, in a first (7, 8) concave recess on one of the two faces (5) of the prismatic body on a section of the circumference of the work roller, wherein the rotational axis of the work roller is inclined at an angle (10), in which the section guided inside the roller cage (1) has a shorter distance to the longitudinal center (C—C) of the prismatic body than the remaining section with a first, groove shaped recess (11) along the longitudinal center (C—C) of the base area (3) of the prismatic body, as a passage for one support roller for the work roller, and a second groove shaped recess (12) along the longitudinal center (C—C) on the side (2) of the prismatic body located opposite the first groove shaped recess (11), for support of the roller cage (1) on the end of the long leg of an L-shaped tool holder, by providing on the second face of the prismatic body (1) located opposite the first concave recess (7, 8), a minimum of one second concave recess identical by position and size to the first concave recess (7, 8).