The color of the stitches on a baseball is traditionally red, and it is unclear why American League manufacturers use waxed red thread. However, the red color is assumed to provide better visual clarity for hand-stitching designers, as it helps guide them through the process.
Those who do hand stitching have decided to stick with the tradition of using red thread.
Another possible reason for the red stitching on a baseball is contrast. The contrast of the red thread against the white cowhide leather helps create a visible line in the air, making it easier for batters to track the ball’s direction as it flies. The red stitching made from wool yarn and black rubber also makes the American baseball ball more visible from a distance.
Many baseball packages, such as those from Rawlings sporting goods, feature heavily red stitching accented by four-ply gray yarn. This creates a distinct raised stitching pattern that is easily visible across the ball’s surface.
