On October 1, 1994, about 1700 central daylight time, a Cessna 188, N731PS, groundlooped during the landing roll at Covington, Tennessee. The airplane was operated by Baker Flying Service under the provisions of 14 CFR Part 137, and visual flight rules. Visual meteorological conditions prevailed. A flight plan was not filed for the aerial application flight. There were serious injuries to the commercial pilot, and the airplane was substantially damaged. Origination of the flight was Covington, Tennessee, about 1615. The pilot reported that the airplane veered left during the landing and that the right rudder pedal and brake did not operate to oppose the divergent ground path. An inspector from the Tennessee Flight Standards District Office, Memphis, Tennessee, spoke with the pilot, and examined the accident site and the airplane, after the accident. He reported that the pilot said he was attempting to land on the runway, and overshot it. The airplane landed in the grass beside the runway. Tire tracks showed a normal landing roll, until about the last 700 feet where the tracks showed the airplane veered left, then entered a skid, breaking off the right main landing gear at the attachment point. The right wing then, struck the ground. According to the inspector, the rudder pedal, rudder cable, and rudder functioned. The brake pad did not exhibit excessive wear and the hydraulic line did not exhibit any pre-impact failure.