World No.1 Novak Djokovic said that he had a "very awkward deja vu" when he accidentally hit a ball at the head of a line judge at during his 6-4, 6-3, 6-3 win in the fourth round of the French Open over Russia's Karen Khachanov.

"My gosh, it was very awkward deja vu. I'm actually trying to find the linesperson and see if he's okay because I saw he had a little bit of a bruise, like redness, in that place in the head where the ball hit him," said 33-year-old Djokovic in the post-match press conference.

"I hope he's fine. I mean, he definitely dealt with it in a very strong and brave way. But it was a hit because I was very close."

At the US Open in early September, Djokovic was defaulted after he angrily hit a female line judge in between points in the throat. The disqualification remains Djokovic's only defeat of the year.

"Obviously, because of what happened in New York, people I guess are going to make the story out of this. It has happened to me and to many other players in the last 15 years that I've been on the tour," said Djokovic.

"I've seen it a lot when the ball ricochets from the racquet and the frame, hits someone in the stands, or someone that is close to you or line umpire. Yeah, it was a very awkward situation."