Yasutaka Uchiyama progressed to the second round of the Japan Open by beating Croat qualifier Franko Skugor on Monday.
Uchiyama, ranked 214th in the world, defeated No. 324 Skugor 6-3, 3-6, 6-1, earning his first win in the main singles draw of an ATP tour event.
Uchiyama broke Skugor's serve in the second game of the first set before rain halted play at Ariake Tennis Forest Park.