MELBOURNE—For two and a half sets, everything went according to plan. Novak Djokovic was up on Denis Istomin 6-3, 6-3, and he had an early break in hand in the third set. Djokovic had done the expected, controlling the points with his returns, his speed, his consistency, and his ability to move his lanky, 6’2” opponent across the baseline without taking many risks. The fact that the man from Uzbekistan was nursing an upper left leg injury was another, unplanned factor in Djokovic’s advantage.

But while Istomin is ranked only 49th, and has never found a way to construct or dictate points against the best players, he’s a shot-maker. Over the last few years, he has taken on the role of night-match foil to the stars. In 2010, he pushed Rafael Nadal in an evening match at the U.S. Open, and last year he did the same to Andy Murray. Both times he wowed the crowd in New York with circus shots, but wasn't a serious threat to pull off the upset. On Friday night Istomin brought his act to Melbourne, but it took him until the second half of the third set to break out the shot-making machine.

Serving at 1-3, and now officially with nothing to lose, Istomin slapped a cross-court forehand pass on the run for a winner and jumped the barrier at the side of the court. A few points later, he held serve with an even better backhand down the line, hit from outside the doubles alley. For the first time in the match, the crowd was engaged; a little momentum, and a lot of the audience, moved over Istomin’s side. With Djokovic serving for the match at 5-4, Istomin earned his first break point, and he converted when Djokovic pushed a nervous forehand into the net.

By this time, Djokovic was annoyed, with Istomin and his crowd-pleasing winners, and with members of the crowd who had distracted him by calling out in the middle of points. Djokovic, more agitated than we usually see him at this stage of a tournament, punctuated winning points with yells in Istomin’s direction, and steely stares into the crowd. If we’re looking for early influences of Boris Becker on Djokovic, maybe we've found one—the young Boom Boom liked to stare people down, too.

Order was soon restored, and Djokovic angrily pushed his way across the finish line to win 6-3, 6-3, 7-5. The stats say he played well: He hit 31 winners against 23 errors, cashed in on five of eight break points, and only faced one of his own. Maybe the half-hour of nerves and testiness were a good thing—Djokovic had gotten his body into this event; now he’s put his emotions into it as well. The next man to face his wrath, and his forehand, will be Fabio Fognini. A more serious test is unlikely: Djokovic is 6-0 against the Italian.