Updated

The LPGA Tour says defending champion and formerly top-ranked Yani Tseng has withdrawn from the Kia Classic after missing her pro-am tee time on Wednesday morning.

In a statement released by the tour, Tseng apologized for what she called "an unfortunate mistake."

She says she wasn't feeling well Tuesday night, overslept and missed her tee time for the pro-am.

Tseng says she was excited to compete this week to defend her title and attempt to regain the No. 1 ranking.

On Sunday, Stacy Lewis ended Tseng's 109-week run at No. 1 when she won the LPGA Founders Cup in Phoenix.