Indian star shuttler P.V. Sindhu opened her BWF Superseries Finals campaign with a fighting win against Akane Yamaguchi of Japan here on Wednesday.In the opening match of the Group B, 2016 Rio Olympic Games silver medallist Sindhu lost the first game 12-21 but came back strongly to bag the next two games 21-8 21-15.With this win, double World Championship bronze medallist Sindhu has taken a 3-1 lead in the head-to-head against the 19-year-old two-time former junior world champion Yamaguchi.On Thursday, world No.10 Sindhu will come across sixth-ranked Chinese Sun Yu, who produced a stunning result against reigning Olympic champion Carolina Marin with a 21-18, 24-22 triumph in 58 minutes.