The tennis world is still trembling in the aftermath of Novak Djokovic’s seismic loss to Denis Istomin down under on Thursday. Although the aura of Djokovic’s invincibility had taken some serious hits since the Serb completed his career Grand Slam at Roland Garros in June, the new year had given some indication that he had righted the ship and turned things around. Rumors of his demise were for certain prematurely exaggerated. Istomin blew that supposition right out of the water. Djokovic, by his lofty standards, had had a poor six months. Upsets by Sam Querrey in the third round at Wimbledon, Juan Martin del Potro in the first round of the Rio Olympics, Stan Wawrinka in the final of the U.S. Open, Roberto Bautista Agut in the semis at the Shanghai Masters, Marin Cilic in the quarterfinals of the Paris Masters, and Andy Murray in the ATP World Tour Finals made for a not so very great body of work. For Djokovic, that is. All but the Querrey and Wawrinka losses were in straight sets to-boot. Of course Djokovic had played at such a superlative level during his 122 week reign at No. 1 that any loss was considered an upset. That’s the rarefied territory he lived in. Two weeks ago, when Djokovic defeated Murray in the final of the Qatar Open, it seemed there might be a return to the old order. New year, new hope, new direction! Not so. Speculation abounds as to what’s led to the decline in Djokovic’s performance level. Some blame the influence of spiritual guru Pepe Imaz, others surmise there’s something going on at home that has diverted his focus. Djokovic himself had hinted at the need to take care of personal issues over the summer after the Wimbledon loss. Other theorists even think it’s his diet, since they say he appeared to look thinner in Melbourne. Personally, I think, as the majority do, it’s burnout — finally hitting the wall after such a phenomenal run. Physically, there’s nothing wrong with Nole. Said former Wimbledon champion Australian Pat Cash: “If we were doubting it before, we confirmed he’s not the same player he was six months ago. [Thursday’s defeat] just shows that Novak has absolutely lost his edge, there’s no doubt about that.” Such a subtle thing is holding an edge. We are used to seeing Djokovic push the pedal all the way to the metal whenever he’s in trouble and grind his way out of danger. Thursday, as on other occasions over the last six months, he failed to floor it when necessary. Didn’t give it enough gas in the clutch moments “When you see someone play as well as Istomin did, it’s usually because their opponent has invited them to deliver their best stuff,” said Craig O’Shannessy, lead analyst for the men’s tour. “When Novak was playing his best, he shut you down, hit the lines, hugged the baseline. There was no space to work in. Now he’s just backed off a tiny bit and he is creating the conditions for the other guy to prosper.” Evidence of dialing it back is the observed decrease in the speed on Nole’s forehand in rallies. In his straight-sets win over Murray at last year’s Australian Open final, official stats noted Djokovic averaged 80 mph on his forehand ground strokes, with a max of 105 mph. Murray’s numbers by comparison were 72 and 92 respectively. Recently, Nole has seen his forehand speed drop to an average of 74 mph and a max of 95. Giving your opponent more time is not a good thing. Erstwhile coach Boris Becker, whom Djokovic departed with in December, offered some insight on the mental side of his former charge after watching his play in Melbourne. “I did not recognize him, his mentality,” Becker said. “He always was very nonchalant about it, and that is not the Novak that I know. I’d rather see him break a racquet or pull the shirt or something, for him to get emotional. I thought it was very even keel the whole match through. That was unusual, and I don’t know what to make of that. I felt he tried, and he played five sets and four-and-a-half hours, but I didn’t see the intensity; didn’t see the absolute will to win, didn’t see him mentally going crazy.” The big question now is whether or not Djokovic will get his mojo back and have the desire to reclaim the top rung in men’s tennis. For someone whom talk of GOAT was being bandied about just six months ago, it’s hard to believe he would pack it in at just 29 years of age. Something tells me he’s going to flip the switch and fight like hell to get it all back again. And in reality, he’s not that far off. Todo esta la cabeza.