WIMBLEDON, England (AP) — Where and when to pop your Champagne is such a Wimbledon problem.

Someone got the timing wrong Sunday at the oldest Grand Slam tournament, where the bubbly helps wash down the strawberries and cream.

“Ladies and gentlemen, please, if you are opening a bottle of Champagne don’t do it as the player is about to serve. Thank you,” Australian umpire John Blom announced just after the start of a match on No. 3 Court.

Anastasia Potapova smiled and nodded in approval. The 22nd-seeded player was serving to start her third-round match against teenager Mirra Andreeva. When she tossed the ball in the air a cork popped and she sent the serve long. She then lost the point on her second serve, and the umpire’s warning followed.

Lanson Champagne is available on the grounds of the All England Club by the glass, half-bottle and bottle. “Le White Label Sec” goes for 95.10 pounds ($122) for a bottle.

“Usually, actually, we buy it here, but it’s quite nice that you can actually bring your own in, which I didn’t realize until my husband looked it up this morning,” said Sarah-Jane Watson, a lawyer from Surrey.

It’s true, you can.

“We brought a bottle,” she said, “and then we bought a bottle.”

They watched matches at No. 2 Court, where a security guard asked that they not open the bottle inside.

A cork was heard popping at Centre Court, though, between points during a match featuring Iga Swiatek and Belinda Bencic.

The 32nd-seeded Marie Bouzkova said she’s too dialed in to be distracted. The Czech Republic native, who lost to Marketa Vondrousova, said during a match a couple of years ago she hadn’t noticed a fire alarm going off in a nearby building.

“I was like ‘what fire alarm?’” she said.

Though there’s at least one place, she added, that’s a bit louder than average: Flushing Meadows.

“In New York,” Bouzkova said, “you have more outside noise, I would say, just from the crowd either drinking maybe too much beer or just being a little bit more loud.”