A motorcyclist from Walker was seriously injured Saturday in a crash near Center Point.At about 5 p.m., Jay Mathews, 61, lost control of his motorcycle while traveling west near 4670 Urbana Road, according to a Linn County Sheriff’s Office news release. Mathews entered the north ditch rolling and was able to crawl to the shoulder to alert help.Walker was taken to a hospital by ambulance with serious injuries.