Serena Williams threatened a lawsuit midway through her fourth-round Wimbledon win over Svetlana Kuznetsova.
The defending women's singles champion was unhappy with the suggestion she and her Russian opponent should play on at 5-5, after light drizzle fell on Centre Court.
She believed it left her open to suffering a slip on the grass that could lead to injury.
After discussing her concerns with umpire Marija Cicak and tournament referee Andrew Jarrett, Williams and Kuznetsova were allowed to leave the court and the retractable roof was moved to provide cover.
Williams won every game from that stage onwards, taking a 7-5 6-0 victory.
When talking initially to Cicak, Williams could be heard to say: "I'm going to fall. I don't get it. Can't they just close the roof?"
Cicak's response was inaudible but Williams added: "If I get hurt, I'm suing..."
A ball boy then ran across the court, and slipped badly on the grass, showing that Williams had valid concerns.
Asked about the on-court conditions in a BBC post-match interview, Williams said: "It was really tricky out there because even though it wasn't raining hard - it was like a dewy - but it's on the grass, you can fall really easy.
"And then it wasn't about that, it was like 'Okay, shall I run for this shot or shouldn't I, because I don't necessarily want to fall', then it became more of a difficulty because of that."