On May 27, 2014, about 1540 central daylight time, an Aero Commander 200 airplane, N200D, collided with an unseen obstruction during a forced landing near La Grange, Texas. The commercial pilot and one passenger were not injured. The airplane was substantially damaged. The airplane was registered to RichAv LLC and was operated by a private individual under the provisions of 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed for the flight. The flight originated from the Lake Charles Regional Airport (KLCH) about 1400.According to a statement made by the pilot, while in cruise at 6,500 feet mean sea level the engine began to run rough. The pilot observed 0 psi on the oil pressure gauge and smoke began to enter the cockpit. The pilot shut down the engine and began maneuvering for the nearest airport. The pilot performed a spiral descent for the airport and descended through the lowest cloud layer at 1,000 feet above ground level. The pilot located the airport and set up to enter the base leg of the traffic pattern. The airplane's descent rate did not allow the airplane to reach the runway and so the pilot performed a forced landing to an open field. During the landing roll, the airplane's nose wheel collided with an unseen hole in the field, resulting in the nose gear collapsing. The airplane's right wing contacted to the ground and was substantially damaged. A postaccident examination of the airplane was conducted by inspectors from the Federal Aviation Administration. Their examination revealed two holes in the crankcase, one above the number 3 cylinder and one above the number 4 cylinder. Damage to the engine was consistent with a loss of oil lubrication. Without the knowledge of the NTSB IIC, the airplane was repaired and the engine disposed of without a thorough examination being completed. The reason for the loss of oil was not determined.