Nishioka edged out Daniel Altmaier 6-4, 3-6, 7-6 (2) in the first round on Wednesday
The Serb will face No 23 seed Tallon Griekspoor in the next round
The American defeated Bernabe Zapata Miralles 6-1, 7-6 (3) on Wednesday
Novak Djokovic is the only big name missing as he skips the Asian swing
The Swiss is a two-time champion at the Shanghai Masters, which returns to the ATP calendar for the first time since 2019