On December 11, 2001, about 1240 hours Pacific standard time, a Piper PA-28-180, N7844W, collided with a runway light and impacted a sign during landing rollout at the Brackett Field, La Verne, California. The airplane was substantially damaged, and the private pilot, who owned the airplane, was not injured. Visual meteorological conditions prevailed at the time, and no flight plan was filed. The airplane was being operated on a personal flight under 14 CFR Part 91. The flight originated from Chino, California, about 1212. The pilot reported that he entered the traffic pattern for landing on runway 26L and everything was normal. The airplane's airspeed was 85 miles per hour, and 25 degrees of flaps were extended. On short final approach he was lined up with the runway. During the landing flare, about 2 feet above ground level, the airplane veered left of centerline. The pilot further indicated that as he started to correct the airplane's left yaw, the airplane "slammed to the ground." Then, the airplane veered off the left side of the runway and collided with runway lights. The pilot also reported that no mechanical malfunction or failure precipitated the accident. The airport manager reported that, based upon his observations of the marks on the runway, the airplane touched down while yawed to the left, about 1/3 of the way down the runway. Skid marks, corresponding to the airplane's three tires, were noted leading off the left side of the runway. The airplane came to rest about 100 feet left of the runway's edge. At 1247 the airport reported its weather was, in part, 20 miles visibility, and few clouds at 9,000 feet. The wind was from 230 degrees at 7 knots. No gusts were reported.