Serena Williams has given birth to her first child. The tennis superstar and her fiancé Alexis Ohanian welcomed a baby girl on Friday (September 1). Her sister Venus Williams confirmed the news to ESPN at the US Open. WPBF (West Palm Beach, Florida) reported that the baby was born at St. Mary's Medical Center in West Palm Beach.

"I'm super excited," Venus told ESPN's Pam Shriver just before her third-round match. "Words can't describe."

Chris Shepherd of WPBF-25 reported that Williams' newborn daughter weighs 6 pounds, 13 ounces--and that mom and baby are “doing well.”

"I'm so thrilled for her, what a role model she's going to be for that daughter," ESPN commentator Chris Evert said during ESPN's broadcast. "I told Serena this: It's a love you've never felt before, and I know she's probably experiencing that right now."

Beyoncé saluted her friend's big news.

Watch Beyonce's Video for "Sorry":

More From KSSM-FM