The pilot reported that prior to landing, the weather reporting system indicated a light and variable wind. While on final approach, the pilot noted that a left crosswind was present. As the tailwheel-equipped airplane was about 2 to 3 feet above the runway, it dropped abruptly onto the runway and bounced. The airplane settled back onto the runway and the pilot noted that he was able to maintain directional control as the airplane slowed down; however, shortly after, the airplane suddenly veered sharply to the right. Despite the pilot's control inputs, the airplane continued to veer to the right and exited the runway surface into soft sand. The left main landing gear collapsed, and the left lower wing struck the ground, which resulted in structural damage to the wing spar. The pilot added that shortly after the accident, the wind was from the southeast at about 15 knots and gusting. The pilot reported no preimpact mechanical malfunctions or failures with the airplane that would have precluded normal operation.