Roberto Bautista Agut made a disgruntled Novak Djokovic pay for another lacklustre display by claiming a stunning victory over the world number one to reach the final of the Shanghai Masters.
An out-of-sorts Djokovic came from a set and a break down to beat Mischa Zverev in the quarter-finals on Friday, but bowed out with a 6-4 6-4 defeat at the hands of Bautista Agut a day later.
Djokovic revealed that humming rather than losing his temper helped him pull off a laboured win against qualifier Zverev, but the 12-time grand-slam champion was unable to conceal his fury as he slipped to a shock defeat to the 15th seed.
The defending champion, attempting to fend off Andy Murray and finish the year at the top of the rankings, smashed his racket, ripped his shirt and sarcastically applauded umpire Carlos Bernardes, with Bautista Agut keeping his cool to beat the Serb for the first time in six attempts.
Bautista Agut will face Murray or Gilles Simon in his first ATP Masters 1000 final on Sunday.
Djokovic, winner of this tournament in three of the last four years, had the first two break-point opportunities of the match in the ninth game but a vibrant Bautista Agut showed great character to hold.
The top seed was smashing his racket after going a set down when he sent a backhand wide in the next game and tore his shirt in anger as he struggled to get going in the second set.
Djokovic clapped Bernardes when he was given a time violation for replacing his torn short with Bautista Agut preparing to serve at deuce and the underdog had the chance to serve for the match after the Serb failed to hold twice.
Bautista Agut was unable to take three match points on serve, but produced a magnificent winner to seize his fourth chance and break Djokovic for a fourth time to pull off a sensational win.