At the conclusion of an uneventful flight, the commercial pilot approached the runway for landing. During touchdown, the airplane veered right and the left wing contacted the runway before the airplane came to rest. During the accident sequence the left main landing gear collapsed and the left wing and fuselage were substantially damaged. Postaccident examination of the airplane revealed that the right main landing gear wheel assembly was free to rotate about the strut, and the bolt securing the torque link had fractured and had a corroded appearance. The landing gear and separated bolt were not examined in further detail.