A teatcup and a teatcup liner are described. The teatcup liner (3) is adapted to be mounted in a shell (2) to form a teatcup (1) to be applied to a teat of an animal. The teatcup liner (3) defines a length axis (4) and an inner space (5) for receiving the teat, and includes a barrel (8) and an upper head (6) for receiving the teat, wherein the barrel (8) has an end portion (12) on which a primary engagement member (13) is arranged. The teatcup liner (3) includes a hindering member (15) arranged on the side of the primary engagement member (13) being distant from the upper head (6), hindering the primary engagement member (13) to bend away from the upper head, wherein the hindering member (15) has a smaller extension from the length axis (4) perpendicular to the length axis (4) compared with the primary engagement member.
