Serena Williams learned a harsh, if not pretty basic, lesson in Rome this week - don't eat dog food.
The 21-time major winner ordered some gourmet dog food to her hotel room - don't worry it *was* for her three-year-old Yorkshire Terrier, Chip - but decided it looked so good that she should try "a spoonful".
Revealing her gaffe on Snapchat, Williams attempted to justify her decision by showing footage of the doggy dish - it was salmon and rice - which left her "running for the toilet" two hours later.
At the start of the Snapchat messages a sheepish Williams says: "So the best thing about Snap is I don't have to hear anybody hating or trolling, because I think this is something you definitely want to hate or troll on."
Kudos, on this front - she was spot on. The rest of the messages, not so much.
"I'm like, what the heck I'm going to try a piece. It looks good, so I eat a spoonful," she said. "Don't judge me I ate a spoonful.
"Let's fast-forward to two hours. I just ran to the toilet like - I thought I was going to pass out."
If it's surprising that Wiliams would eat dog food it is even more of a mystery given the care with which professional athletes must take with what they consume.
Earlier this year Maria Sharapova announced she had returned a positive drug test during the Australian Open and was provisionally banned.
To be fair it's hard to imagine eating dog food is performance enhancing - although Williams did recover to beat fellow American Christina McHale 7-6 (9/7) 6-1 today - and certainly she won't be repeating the dining experience.
"It did taste weird, I forced swallowed it," added Williams, who also revealed she paid 15 euro for the dog food.
"It tasted a little bit like a house cleaner type of thing. I don't know what they put in this dog food, but Chip liked it and it looked good.
"I don't think it's consumable for humans. They should have wrote that."