Wimbledon chiefs downplayed concerns over dampness on Centre Court on Tuesday despite a long delay during Novak Djokovic's first-round match on the opening day of the championships.

The seven-time champion, chasing a record-equalling 24th Grand Slam title, defeated Argentina's Pedro Cachin in straight sets on Monday.

But the clash was delayed for nearly 90 minutes after the conclusion of the first set, even though the roof was deployed due to rain, with multiple inspections by officials and players before play resumed.

Defending champion Djokovic at one stage emerged with a towel, which he used to rub the surface of the court, to laughter from the crowd.

Members of the groundstaff then used hand-held leaf blowers to try and dry the surface in farcical scenes on the world-famous court.

"They were also very confused about what's going on," Djokovic said after his match. "I guess they will check that.

"Hopefully they'll fix it because that's one of the only two courts that has a roof. If it starts raining, if you can't play under the roof, that's a little bit of an issue for the schedule."

Later in the day, five-time champion Venus Williams suffered a nasty fall on the same court, hurting her already-bandaged right knee.

"I was literally killing it, then I got killed by the grass," said the 43-year-old after her loss to Elina Svitolina.

Wimbledon operations director Michelle Dite, however, said organisers were not planning to do anything different on Tuesday.

"We're playing on a living surface and that's one of the wonders of grass and it's what we look after 365 days a year with our head groundsman, all of the staff, making sure that when we get to the championships, it's at its pinnacle," she said.

Dite said there was more moisture in the grass than expected.

"There was nothing strange," she said. "It was a set of circumstances with the environmental control in the bowl. There is nothing that's broken. There is nothing that means we're not confident in playing today."

Dite apologised to supporters who waited for hours in the queue for entry to the All England Club on Monday, partly due to enhanced security checks over fears of protests by climate activists.

She said changes had been made in an effort to make the process smoother.

"We had about 11,500 people through the queue yesterday," she said. "We had our highest attendance at the championships on day one since 2015. 

"Lots of reasons why the demand was so high -- ballot uptake was incredible, hospitality sold out. 

"We pride ourselves on being a very open and accessible event so the only way really you can get a ticket at the moment is through the queue. Obviously big excitement, a lot of people turned up."

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