World number one Rafael Nadal produced a masterful display to overcome Croat Marin Cilic 7-5 7-6 (7-3) and reach the Shanghai Masters final.
Cilic, who will rise to a career-best fourth, created three set points after early pressure from the Spaniard, who won the opener in 67 minutes.
Nadal, seeking a seventh title of 2017, was broken twice in the second but won a fine match in two hours 11 minutes.
Roger Federer contests the second semi-final with Juan Martin del Potro.
In the first semi-final, the opening game provided much entertainment as it fluctuated during a 10-minute spell in which Cilic had served at 40-0.
Cilic’s first two service games comprised 30 points, while Nadal conceded only three points in his first four games on serve.
But Cilic, the 2014 US Open champion and beaten finalist at Wimbledon this year, gradually imposed himself on proceedings and a crunching forehand down the line from the back of the court earned two break points.
He was unable to take those as Nadal demonstrated his powers of resolve and the Croat, having saved six break points, eventually conceded the only break of the set.
US Open champion Nadal broke in the third game of the second set after Cilic netted two volleys but then lost his own serve as his drop volley also went into the net.
Cilic saved three break points in game nine but then a stunning whipped Nadal forehand down the line on the run created a break that he duly seized.
Cilic was not finished, however, and after saving a match point he dispatched more powerful shots from the baseline to break again.
Nadal, bidding to win the Shanghai title for the first time, calmly served out to force a tie-break and the Spaniard completed his fifth victory in six matches against Cilic, his 16th consecutive victory in all tournaments.