World number one Novak Djokovic says that he cannot guarantee he will not make a similar mistake to his disqualification at the U.S. Open for striking a line judge with a ball but that he would try his best.

The Serb was disqualified in the fourth round in New York after he hit a ball in frustration after dropping serve in the first set against Spain's Pablo Carreno Busta, hitting the line judge in her throat and causing her to fall to the floor.

Djokovic said that he called on the lineswoman to check on her health since the incident at Flushing Meadows.

"It's not completely out of the blue," Djokovic told a news conference at the Italian Open.

"I cannot promise or cannot guarantee that I will never ever do anything similar to that in my life. I'm going to try my best, obviously, but anything is possible in life."

Following the incident, the tournament organisers confirmed Djokovic was fined $250,000 -- his prize money for reaching round four. The 33-year-old was also fined an additional $10,000 for unsportsmanlike conduct.

"The rules are clear. I accepted it and had to move on. That's what I did," Djokovic added.

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