The Yomiuri Giants won nine straight Nippon Series championships from 1965 to 1973. Five times during that stretch (1967-69, 1971-72), their opponent in the Series was the Hankyu Braves, managed by Yukio Nishimoto. In addition, Nishimoto and the Braves won the second half crown in 1973 (the first year the Pacific League used a split season), but lost in the playoffs to Katsuya Nomura and the Nankai Hawks. Following this loss, Nishimoto and the Braves parted company and he took over the Kintetsu Buffaloes, leading them pennants in 1979 and 1980. The Buffaloes were defeated in the Nippon Series both times by the Carp. In addition, prior to managing the Braves, Nishimoto led the Damai Orions to the Pacific League pennant in 1960, only to lose in the Series to the Taiyo Whales. So that's eight trips to the Series with no Championships.
Gary Engels and Rob Fitts describe him in "Japanese Baseball SuperStars" as the "Marv Levy of Japan". Here's his card from the 2009 BBM Hankyu Memorial set (#01):
(For the record, the V9 Giants other opponents were Kazuto Tsuruoka's Nankai Hawks in 1965-66, Wataru Nonin's Lotte Orions in 1970 and Nomura's Hawks in 1973.)