The commercial pilot had recently purchased the tailwheel-equipped accident airplane and was receiving flight instruction in it toward a tailwheel endorsement, and had previously completed two successful landings. During the third landing, in a 12 to 14-knot right crosswind, and just as the tailwheel was about to settle onto the runway, the airplane began to veer to the right side of the runway. The pilot attempted to compensate by applying full left rudder, as did the flight instructor, but the airplane continued off the right side of the runway and into the grass. Before coming to rest the left main landing gear collapsed and the left wing struck the ground, substantially damaging it. Following the accident both the pilot and the flight instructor reported that there were now preimpact mechanical malfunctions or failures of the airplane that would have precluded normal operation, nor was any found during a postaccident examination of the airplane conducted by a Federal Aviation Administration inspector.