'He's going to be the bad guy the rest of his career,' says John McEnroe of Novak Djokovic

Novak Djokovic hitting a line judge with a ball has become one of the enduring images of an already bizarre season of tennis.

The 17-time grand slam winner was disqualified from the U.S. Open, a tournament he was favourite to win to close the gap on Rafael Nadal's total of 19 grand slam wins and Roger Federer's 20.

With the French Open set to start at the end of the month, the world No.1 still has an opportunity to add to his all-time tally during this curtailed season -- but has the Serb tarnished his reputation?

Seven-time grand slam champion John McEnroe, who was famous for his on-court outbursts, believes the incident will have an impact.

"The pressure just got to him I think," McEnroe, himself disqualified from the 1990 Australian Open for misconduct, told ESPN. "... Now whether he likes it or not, he's going to be the bad guy the rest of his career. It'll be interesting to see how he handles it."

"I didn't say he couldn't recover," added McEnroe. "If he embraces that role, I think he could recover, absolutely. He's chasing history, he's trying to pass Rafa [Nadal] and Roger [Federer].

"He's younger, we all know that. He's got a lot of things going for him, but this is obviously a stain that he's not going to be able to erase, whether he likes it or not."

Djokovic left Flushing Meadows without speaking to the media, but did write an apology on his Instagram account, saying he was "extremely sorry to have caused her such stress."

McEnroe knows all too well how hard it is to shake a "bad boy" reputation in tennis and is surprised somebody with as much experience as Djokovic would make such an error.

"Just when you think something crazier couldn't happen [in 2020], it does happen," he added. "We talked before the event that the only way Novak could lose is if he beat himself.

"I didn't anticipate in my wildest dreams that this would happen. So it's terrible for everyone, it was a rookie mistake."

The disqualification is the latest incident during what has been a difficult summer for Djokovic. First, he arranged a tournament in Croatia which failed to observe social distancing regulations and resulted in him and a number of top players testing positive for COVID-19.

Then, he spearheaded a new breakaway players' association, the Professional Tennis Players Association (PTPA), drawing criticism from Federer and Nadal.

Nick Kyrgios, often dubbed the "bad boy" of tennis' current generation, posted a tongue in cheek Twitter poll asking what his punishment would have been in the same situation.

"Swap me for jokers [Djokovic's] incident. 'Accidentally hitting the ball kid in the throat,' how many years would I be banned for?" he asked.

Five, 10 and 20 years were the options, with 20 winning by a considerable margin at the time of writing.

"We'd be bailing you outta jail right now," American player Tommy Paul responded.

Former British tennis player Tim Henman, who was disqualified in similar circumstances when he hit a ball girl at Wimbledon in 1995, believed Djokovic made a mistake by not facing up to the media following the incident.

"Unfortunately he's compounding the error," he told Prime. "He needs to face up to it, apologize and accept he made a mistake. By, in essence, running away, it's going to go on longer."

Billie Jean King, a 12-time grand slam winner, said the officials made the right decision.

"First I hope the line judge is okay," she tweeted. "The rule is the rule. It is unfortunate for everyone involved, but in this specific situation the default was the right call."

Djokovic was unbeaten so far in 2020, boasting a 26-0 record going into Sunday's match against Pablo Carreno Busta. Former tennis player Steve Darcis jokingly gave credit to the one person who was able to break Djokovic's winning run -- the line judge.