KOBE, Japan (AP)—Kei Nishikori beat Denis Istomin 6-7 (5), 7-5, 6-4, 6-3 on Sunday to give Japan an unassailable 3-1 lead over Uzbekistan and a place in the Davis Cup World Group playoffs in September.
Nishikori won all three of his Asian/Oceania Group 1 matches against Uzbekistan—two singles and one doubles—to give Japan the chance of reaching the top-tier World Group for the first time since 1985.
The 50th-ranked Nishikori was playing in the Davis Cup for the first time in two years.
The 21-year-old Nishikori improved his Davis Cup record to 5-1 and will compete in a World Group playoff for the first time in his career. Japan has failed three times to break into the World Group since 1998, against Russia, Chile in 2004 and Romania in 2007.