An obligatory article about Denis Istomin

Denis Istomin was not playing well. In the final of his home tournament in Tashkent, Uzbekistan, he found himself down a set and a break in the second set to Konstantin Kravchuk. He went down quietly. Kravchuk served a bevy of aces and took the match 7-5, 6-4. The few people who had even showed up for this minute Challenger event must have been disappointed, but it was hardly a surprise.Istomin, now at age 30, had struggled with his health, losing two matches to retirement within since May. He would retire again in a loss to Steve Darcis two weeks later. His ATP ranking, once a stellar 33 in August 2012, had now fallen to 144.Yesterday, Denis Istomin defeated Novak Djokovic.For someone who tries to watch as much tennis and various minor sporting events as he can (shout-out to late-night WCC basketball not involving Gonzaga and Saint Mary's), I have no clue how Denis Istomin produced this level of tennis. The main problem with Istomin, having watched him play on a few choppy Challenger streams in Astana, Budapest and Bratislava, was that he hit far too many unforced errors. His serve was decent, but nothing special. He struggled on clay. He was far from clutch. He lost two Challenger finals. Early in 2016, Istomin lost 9 straight matches.He only made the Australian Open by qualifying through the Asia-Pacific Wildcard Playoff. In the semifinal against Prajnesh Gunneswaran, Istomin saved three match points on Gunneswaran's serve. He finally won the final set 11-9 and then blasted Duck Hee Lee in the final. I thought Duck Hee Lee would win.Whenever you watch a Challenger event, you are struck by two things. One is that a lot of the players are actually decent (Diego Schwartzman, Steve Darcis, Lukas Lacko, etc.). The shot-making is still world-class. The big servers, your Sam Groths or Uladzimir Ignatiks, can still serve.The second point is that there's a sense that a player like Andy Murray or Novak Djokovic would still absolutely wreck all of these Challenger players. And they do. There just isn't much consistency on the Challenger Tour. Watching Istomin constantly get the ball back in play again and again last night was nothing short of a miracle. And to pull it off in a grueling, nearly five-hour, five-setter is flabbergasting. Istomin couldn't hold it together for a set against Nicholas Almagro in Genova. He lost a set to Denys Molchanov. He dropped a five-setter in the Davis Cup to Ze Zhang.Istomin was awe-inspiring in the fourth and fifth sets. In the fourth-set tiebreak, he was magnificent. He was smacking return winners off Novak that only guys like Del Potro or Wawrinka could manage. He hit an ace at 6-5 on his own serve to seal the set. In many ways, it was similar to how Wawrinka beat Djokovic in the US Open Final or how Del Potro defeated him in the Olympics.You cannot really imagine what it felt like to play through that match. His whole career, realistically, could be forever immortalized with just a few games. Robin Soderling, Lukas Rosol, heck, even Nick Kyrgios, had made names for themselves for one huge match in a Grand Slam. But Istomin felt no pressure. He laughed off bad things happening to him. After nearly serving an ace in the fifth that went for a let, he started walking off the court for no reason."I thought you said 'game Istomin'," he said to the chair official."No, I said let first service," she replied."Oh, sorry."Maybe after the most difficult year of his career, a year spent losing badly to bad opponents and even worse losses to top players, a year spent injured, sore and on flights from Kazakhstan to Eastern Europe and back, Istomin accepted his fate. The role that he would play, while somewhat in his control, still could never fall into strict order. Or maybe he's just a happy-go-lucky guy. Somehow, he mentally stayed tough and Djokovic, the reigning champ, the unstoppable force, folded.Djokovic, for a while, was able to reflect raw power and outlast his opponents. He could outlast Gilles Simon despite over 100 unforced errors. He could deflect the raw power of a Raonic (8-0 H2H) or Berdych (25-2 H2H). He could just outplay anyone who tried to beat him at his game (Nishikori+Goffin, 16-2).Now, I have no idea. If he can get out-muscled by Denis Istomin, who serves 190 km/h, hits decent groundstrokes and can't play at the net at all, then what's going to happen when Djokovic plays someone like Jack Sock or Alexander Zverev? The matchup goes from "no chance" to "you never know".Djokovic has played some crap matches over the last few months:

• Lost to Sam Querrey at Wimbledon: just an awful, passive performance. He broke to nearly take the fourth and let Sam Querrey break him back.
• Lost to Wawrinka in the US Open Final: Wawrinka didn't exactly play his best tennis until the third, but by then Djokovic was just totally checked out. The injury scares in the fourth were pitiful to watch, not out of hatred, but because it seemed like something had broken both mentally and physically.
• Win over Mischa Zverev in three sets in Shanghai: Although Djokovic won, he nearly lost to a limited serve and volleyer nearing 30. Zverev took him to a second-set tiebreak and nearly broke through in the third, but he couldn't keep it up.
• Loss to Robert Bautista-Agut in the Shanghai semifinal: Djokovic was just horrendous in this match.
• Lost to Marin Cilic in the Paris Masters: Cilic played quite well, but this isn't the Marin Cilic of 2014. Cilic, who also lost in the second round to Dan Evans, has been wildly inconsistent and struggled mentally. Yet Cilic held strong in Paris and Novak did not.
• Loss to Murray in Tour Finals: Another awful performance from Djokovic.
• Win over Fernando Verdasco in Doha: Verdasco, by all rights, should've won this match with 4 match points in the second-set tiebreak. He choked because he's Verdasco.

Djokovic played much better on Wednesday than he did in any of these matches. I watched all of them except for the Verdasco collapse. Djokovic played at a high level and still lost to Denis Istomin. It doesn't make sense. After all, Djokovic had just ended Murray's massive win streak in Doha a couple weeks ago.I hesitate to mark Djokovic as "done". These losses happen. Andy Murray lost to Federico Delbonis in Indian Wells back in March (a three-setter, but still, it's Delbonis). Nadal lost to Lukas Rosol at Wimbledon. Federer got knocked out by Sergiy Stakhovsky once. Djokovic had an incredible run of luck during his run of greatness and he's regressing to the mean. It makes sense that he's regressing so much, due to the sheer dominance of his streak, but with Djokovic aging and Murray's dominant stretch looming, it's safe to say "invincible Djokovic" is probably done (for now).