'This is insane': Fans in shock over 'crazy' scenes at US Open

The US Open was rocked by crazy scenes on Wednesday when torrential rain and wind caused delays on indoor stadiums.

Play in the second-round match between Kevin Anderson and Diego Schwarztman on Louis Armstrong Stadium was halted because wind was blowing the rain through an opening between the concourse and the arena’s retractable cover.

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The players left the court at 5-5 in the first set, with volunteers attempting to dry the surface.

However they were forced back off in the second set when the court again became too wet, with Anderson forcing the hand of officials by storming off.

"You guys call me when you're ready to play tennis," the South African said before leaving the court.

The match was eventually suspended with Schwartzman leading by one set and 1-0 in the second, with play on that court called off for the night.

Wednesday's last scheduled match in Armstrong between Angelique Kerber and Anhelina Kalinina was postponed until Thursday.

The US Tennis Association said the area is under a tornado watch with potential for lightning.

The loud rain pounding on the roof of Arthur Ashe Stadium for Stefanos Tsitsipas' clash with Adrian Mannarino made it tough to hear the players’ racquets smacking the tennis balls.

Fans in the upper sections of the stadium were also forced to put up umbrellas up when rain started coming through gaps in the roof.

One commentator declared they'd "never seen anything like it".

"You can't play in this, crazy," said Jason Goodall on ESPN.

"I'm surprised they've even played that point there.

"You can see very clearly it's coming in through the ventilation on both sides, it's just whether it's falling enough on court to stop play. If one of the players in this situation thinks it's unsafe then you've got to be fair to both.

"The rain and wind have made things unplayable. Everybody's got umbrellas up in the crowd because it's going sideways then dropping onto the court. It's turned into a bit of a shambles."

Fans flocked to social media in disbelief over the "insane" spectacle, with the deluge also causing flooding in the grounds at Flushing Meadows and closing subway stations around New York.

Minimal play was possible on outside courts on Wednesday because of the weather, which came after Hurricane Ida slammed into the US Gulf Coast at the weekend.

Sloane Stephens overpowers Coco Gauff

Earlier, 2017 champion Sloane Stephens pulled away for a 6-4 6-2 victory over 17-year-old Coco Gauff.

Afterward, the pair met at the net for a warm hug before Stephens praised the player - and person - Gauff has become.

"I love Coco. I think everyone knows I love Coco. At the end of the match, I said, 'I love you'," Stephens told the Arthur Ashe Stadium crowd.

"She's such a great player and I feel so lucky to have seen her grow up and play since she was eight.

"I know there's going to be great things ahead for her."

With the roof shut during the heavy downpour, the thump-thump-thump of the rain created a bass beat that drowned out the usual sounds of a tennis match.

In the second set, 21st-seeded Gauff failed to convert on the only break point opportunity she had against the 2017 Flushing Meadows champion, who had eight forehand winners across the one hour and six minute meeting.

"The forehand was key today," 28-year-old Stephens said.

"I wanted to come out here and really execute and play my game."

with agencies