Novak Djokovic, the world No 1, admitted he had felt “very awkward deja vu” after slamming a ball into a line judge for the second consecutive tournament. This time, though, there was no action from the officials, and no suggestion that he was at fault.

Djokovic was disqualified from the US Open when his irritated slap at a spare ball happened to connect with the throat of lineswoman Laura Clark. Such accidents are viewed as automatic defaults, because there is no need to go around hitting balls that are not in play.

The difference on Monday at the French Open was that Djokovic was trying to return the monstrous serve of Karen Khachanov, which has been known to exceed 130mph. The ball skewed off the tip of his racket into the temple of the judge watching the service line.

“My gosh, it was very awkward deja vu,” said Djokovic, who still disposed of Khachanov in straight sets with his latest commanding performance. “I’m actually trying to find the linesperson and see if he’s OK because I saw he had a little bit of a bruise, like redness, in that place in the head where the ball hit him.

“I hope he’s fine. It was a [painful] hit because I was very close. Obviously, because of what happened in New York, people I guess are going to make a story out of this. [But] it has happened to me and to many other players in the last 15 years that I’ve been on the tour.”

Djokovic just sniped another line judge

— Gump Cathcart (@bubbagumpino) October 5, 2020
Such occasional, but inevitable, mishaps would be eliminated if automated line-judging – recently used on the outside courts at the US Open – were to be introduced in all elite tournaments. Indeed, Djokovic had recommended exactly this after his previous win on Saturday.

Meanwhile, Germany’s Alexander Zverev, the world No 7, took to social media on Monday night to confirm he had tested negative for Covid-19 – a result that will surely come as a relief to Jannik Sinner, the 19-year-old Italian who had knocked him out on Sunday.

Zverev was suffering from heavy-cold symptoms during that match, which created much debate. Had they turned out to have been caused by Covid, then Sinner would probably have been sent into self-isolation and thus eliminated from the tournament through no fault of his own.

Zverev earned heavy criticism on Sunday for not admitting that he arrived on site with a 38-degree temperature and such bad congestion that he would later cough and splutter his way through his post-match press conference.

On Monday night, he added that he had not spoken to doctors himself before the match. “There was no obligation to indicate whether one was ill or not,” he told Eurosport Germany’s Matchball Becker programme.

This was inaccurate. The French Open’s medical protocols stated that players should show a “sense of duty and responsibility”, adding that anyone with symptoms that could indicate Covid-19 – such as breathing difficulties or a high temperature – “must adopt a responsible attitude and not attend the stadium”.

Zverev also confirmed on Monday that Hugo Gravil, his physio, had sought anti-cold medication from the tournament doctors after his win over Marco Cecchinato on Friday night.

Given the concerns around this tournament, and the “circuit breaker” lockdown that has been imposed on Paris this week, Gravil’s request should probably have triggered a more proactive response from the French Tennis Federation.