The pilot stated that he was practicing touch-and-go landings on runway 23 at Greenville, SC, airport, and he believes that a sudden crosswind from the right lifted the light sport airplane's wing abruptly, and caused his foot to slide off the right rudder pedal, unknowingly onto the copilot's left rudder pedal. He further stated that at that time he depressed the pedal which caused the airplane to veer to the left, and depart the runway while airborne. He said he was unable to "straighten the nose back to the original heading and lift the left wing with what was believed to be right rudder", and the left wing impacted the ground. Upon examination of the cockpit after the accident, the pilot said it was readily seen that pilot's right rudder pedal was too close to the copilot's left rudder, without any partition separating them. He also said that none of the rudder pedals had foot-guards to prevent feet from sliding off the pedals, and that there were no mechanical failure or malfunctions to any of the airplane's systems.