RIZIN 45 is officially on the calendar, and it features a handful of names notable to American viewers. The event takes place Dec. 31 at Saitama Super Arena in Saitama, Japan, the promotion announced at a news conference Thursday. Atop the billing will be two title fights. An inaugural RIZIN flyweight title has been implemented as former Bellator bantamweight champion Kyoji Horiguchi (31-5) battles Makoto Shinryu (16-1-1).