Novak Djokovic smashes racket in furious outburst at Italian Open - in pictures

Two weeks after US Open disqualification, Serb loses his cool again and gets a warning from the umpire

Serbia's Novak Djokovic smashes his racket against Germany's Dominik Koepfer during their quarterfinal at the Italian Open in Rome. AP

Novak Djokovic walks to change his broken racket. AP

Serbia's Novak Djokovic serves to Germany's Dominik Koepfer at the Italian Open in Rome. AP

Novak Djokovic of Serbia celebrates victory. Getty

Novak Djokovic checks his broken racket. AP

Novak Djokovic during the match. Getty

Novak Djokovic in action against Dominik Koepfer. EPA

Djokovic and Koepfer after the match. EPA

Novak Djokovic of Serbia in action. EPA

Novak Djokovic's frustration boiled over once again as he smashed his racket in a fit of rage during his 6-3 4-6 6-3 win over Dominik Koepfer in the Italian Open quarter-finals.

The top-ranked Serb was broken to love in the sixth game of the second set and he threw his racket on the ground, drawing a warning from the umpire, less than two weeks after being disqualified from the US Open.

"Well, let me tell you it's not the first nor the last racket that I'll break in my career," Djokovic, 33, said. "I have done it before, I'll probably do it again. I don't want to do it, but when it comes, it happens.

"That's how I guess I release sometimes my anger. And it's definitely not the best message out there, especially for the young tennis players looking at me.

"I don't encourage that, definitely. But, look, we're all people. We all do our best. There were times and periods when I don't do that, and there are periods when I do," he said.

The Serb was disqualified from the US Open after inadvertently hitting a ball into a line judge's throat during his fourth-round match against Pablo Carreno Busta.

Djokovic's red mist

Djokovic, who apologised at the time and vowed to take away valuable lessons from the incident, reiterated that he was working on his "mental and emotional health" to try and help keep a lid on his emotions.

"It's always been part of my, I guess, training and recovery, as well, developing strong character and understanding myself on different levels, holistic approach to life," the 17-time Slam champion said.

"That's just me. Of course I'm not perfect. I'm doing my best."

Djokovic, who faces Norway's Casper Ruud in the semi-finals, will fancy his chances of sealing a record 36th Masters 1000 crown following nine-time champion Rafa Nadal's shock exit at the hands of Diego Schwartzman.