A furious Novak Djokovic smashed a racket and tore his shirt in a shock 6-4 6-4 semifinal defeat to Roberto Bautista Agut at the Shanghai Masters. br br The world No. 1 initially lost his cool when a stray backhand gifted Agut the first set, splintering his racket at the back of the court. br br That was followed by the Serb ripping the neck of his shirt open after an attempted passing shot dropped into the net, giving Agut break point in the second set. br br Djokovic received a time violation while changing into a new shirt, further incensing him and he was scathing in his criticism of umpire Carlos Bernardes after the match. br br "He was the star of the show," Djokovic told reporters. "That's what he wanted to be today." br br The 29-year-old, who has won in Shanghai three times, suggested fatigue played a part in his on-court outburst. br "There are definitely things that I need to regain from the emotional, mental point of view. br br Read: Controversial Kyrgios fined for 'lack of effort' br "So I guess I'm focusing on that more. It's a transition somewhere in between, maybe just exhausted by the amount of matches I have had in the last 15 to 20 months. br br "Maybe all in all that's the cause of me feeling this way. I had to experience this sooner or later. I knew I could not go on playing at the highest level for so many years all the time." br br Djokovic's first ever defeat to Agut opened the door for Andy Murray to close the gap at the top of the world rankings.