(CNN) Who let the dogs out?
It wasn't Serena Williams but the world No. 1 is regretting eating some of her beloved canine's food.
Williams ordered the meal for three-year-old Chip -- a Yorkshire Terrier -- at the hotel she was staying at during the Italian Open in Rome. The salmon and rice mix -- which cost $17 -- looked so good, she said, that the 21-time grand slam champion decided to give it a try.
Wrong move as she quickly became ill and had to run to the bathroom.
"Before you judge me, look at it," Williams said on Snapchat in a video that was later posted on YouTube, panning to the salmon and rice. "Come on. It looks good. In fact when I take the food to go, they give me the same food package.
"It comes with the expensive looking spoon. I'm like, 'What the heck? I'm going to try a piece.'"
She took a spoonful.
"Let's fast forward two hours," she continued. "I just ran to the toilet. I thought I was going to pass out. It did taste weird.
"I force swallowed it. It tasted a little bit like a house cleaner kind of thing. But Chip liked it and it looked good."
Later looking distraught, Williams added: "I really don't feel so good."
However she appeared in better spirits not long after and joked: "I need a life."
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The incident didn't stop Williams taking to the court for her next match and defeating fellow American Christina McHale 7-6 (9-7) 6-1 to reach the quarterfinals, where Svetlana Kuznetsova -- a two-time grand slam winner who upset her in Miami in March -- awaits Friday.
Rome is only Williams' fourth official event of 2016 after she skipped three tournaments because of the flu.
In less than two weeks at the French Open, Williams begins her quest for a 22nd major. If successful at Roland Garros this spring she would tie Steffi Graf's Open Era grand slam record.
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