On March 29, 2001, about 1030 hours mountain standard time, a Piper PA18-150, N9299D, was substantially damaged during landing rollout at Holbrook, Arizona. The private pilot was not injured. Visual meteorological conditions prevailed for the personal flight, operated by the pilot under 14 CFR Part 91. No flight plan was filed. The flight originated at Buckeye, Arizona, on the morning of the accident, and was destined for Farmington, New Mexico, with a stop at Holbrook. The pilot reported that when he landed on runway 21 the wind was out of the east about 10 knots. During touchdown the airplane immediately veered right 90 degrees, and exited the runway into sage brush coming to rest on the nose. No official weather was available for the location. The pilot also reported that the lower rudder hinge point had separated from the vertical tail post. The steerable tail wheel is attached to the rudder horns near that hinge. Pictures of the failure were included in the pilot's report.