Novak Djokovic delivered an extraordinary display of self-inflicted frustration during his Wimbledon second-round encounter this afternoon, repeatedly striking his own thigh eleven times whilst seated during a changeover on Centre Court.The 39-year-old Serbian had appeared entirely dominant after securing the opening two sets against France’s Arthur Rinderknech, yet his composure disintegrated spectacularly in the third.The 25th seed transformed the contest through heightened aggression, breaking the seven-time champion’s serve twice to establish a commanding 5-0 advantage.Djokovic stretched out his troublesome leg before thumping it repeatedly, seemingly attempting to rouse himself from his sudden collapse.Novak Djokovic started hitting himself during a break in play | REUTERSBBC commentator Andrew Cotter expressed his astonishment at the sudden turn of events, telling viewers: “Did not see this coming.” As the seventh seed began hammering his thigh, Cotter winced audibly before quipping: “Oof, hang on… That’ll fix it.”Former British player Kyle Edmund, providing analysis alongside Cotter, offered a wry observation: “Not seen that technique before being used.”Cotter subsequently addressed the underlying concern with greater seriousness, noting that physical decline becomes inevitable at Djokovic’s age.”They are the things that will go when you’re 39 years old. Just, you haven’t quite got that acceleration, that movement, you’re just starting to feel a little bit heavy,” he remarked.Rinderknech’s third set proved nothing short of remarkable, wrapping up proceedings 6-1 in a mere eighteen minutes.Novak Djokovic admitted after the win that he was stressed | REUTERSThe Frenchman sealed victory with his seventh ace of the set, prompting Tim Henman to deliver glowing praise from the commentary box.”83 per cent first serves, seven aces, 93 per cent [first serves won]. Just fantastic stats all around,” Henman observed. “I mean, that’s got to go down as one of Rinderknech’s best sets of tennis in his career. 13 winners, two unforced errors. Happy days.”Djokovic came perilously close to suffering his first-ever whitewash on grass, falling 0-30 behind whilst serving to avoid the dreaded bagel.The Serbian’s left thigh difficulties persisted into the fourth set, where he was observed tapping his racket against the troublesome limb whilst awaiting a return at the baseline, holding a 2-1 advantage on serve.This represents merely the eighth occasion in Djokovic’s illustrious career that he has conceded a set by such a margin on grass courts.The exclusive company of players to have inflicted a 6-1 defeat upon him on this surface includes some of the sport’s greatest names: Roger Federer, Rafael Nadal, and the current world number one Carlos Alcaraz.