On June 6, 1999, at 0900 mountain daylight time, a North American SNJ-4, N99DA, sustained substantial damage when the right main landing gear collapsed as the aircraft departed the side of the runway during landing roll at Alexander Municipal Airport, Belen, New Mexico. The commercial pilot and sole occupant was not injured. Visual meteorological conditions prevailed for this flight operating under Title 14 CFR Part 91. The flight departed Santa Fe, New Mexico, at 0830. According to the pilot, the landing at Belen was a normal wheel landing. He said the aircraft began to drift to the left during landing roll and he applied right rudder and brake to correct the drift. The aircraft straightened out for about 2,000 feet of travel and then veered hard left. The pilot said the application of full right rudder and brake did not correct the swerve and the aircraft departed the left side of the runway into soft sand, causing the right main landing gear to collapse. In addition, damage was done to the outer portion of the right wing. Post-accident inspection by a mechanic revealed a binding in the left brake and wheel assembly.