Abstract: A shape retainer and a shape retention method are provided, by which the shape of an interior space of an inner part of a baseball or softball glove can be retained precisely. A shape retainer includes a main body having a main surface depressed in a concave shape, so that the shape of the interior space of the inner part of the baseball or softball glove can be retained precisely.

Abstract: The baseball or softball glove includes a thumb part, an index finger pan, and a web. The web includes a first protrusion and a second protrusion. The first protrusion has a first through hole. The second protrusion has a second through hole. At least either the first through hole or the second through hole has an inclined edge that extends obliquely upward from a base of the thumb part or the index finger part on a peripheral edge forming the through hole. The first protrusion and the second protrusion are engaged with each other in a state where the first through hole and the second through hole are connected to each other in a chain shape.