Last year's Australian Open champion, Sofia Kenin, says she had her appendix removed this week.

The 22-year-old American posted on Twitter on Wednesday that she went to see the tournament doctor this week with “acute abdominal pain.”

She wrote that the doctor sent her to a hospital, where she was diagnosed with acute appendicitis after a medical scan and had surgery on Monday.

Kenin lost to Kaia Kanepi in straight sets in the second round of her title defense at the Australian Open last week.

Kenin then dropped her opening match at a lower-level WTA event held at the same site in Melbourne against Australian teenager Olivia Gadecki on Saturday.