Long-time rival Roger Federer takes on Juan Martin del Potro in the tournament's other semi-final.
Rafael Nadal powers past Marin Cilic to reach Shanghai Masters final
Rafael Nadal survived a rollercoaster encounter with fourth seed Marin Cilic to power into Sunday's final of the Shanghai Masters and a possible showdown with old rival Roger Federer.
The Spanish world No 1, who has never won the tournament but is on a terrific run of form, finally saw off the Croatian after saving three set points in the opener on the way to a tense 7-5, 7-6 victory.
World No 2 Federer plays Juan Martin del Potro in the other semi-final later on Saturday after the Argentine said he was fit despite hurting his wrist in a fall in the quarter-finals.
In other tennis news, former world No 1 Maria Sharapova reached her first final since returning from a 15-month doping ban in April after a 6-3, 6-1 win over local favourite Shuai Peng.