A flyweight bout between top contender Brandon Royval and fifth-ranked Tatsuro Taira  headlines Saturday’s UFC Vegas 98 fight card at the UFC Apex in Las Vegas.   Royval (16-7) enters the bout coming off a win over former two-time titleholder Brandon Moreno . The former title challenger has won four of his last five fights. Taira (16-0) brings with him an undefeated record.