Australian tennis player Lleyton Hewitt and his wife Bec Cartwright had a baby daughter on Tuesday, Tennis Australia announced.

The couple's first child was born in Sydney on Tuesday morning. The girl has not been named yet.

"Lleyton and Bec are absolutely thrilled," the couple's manager Rob Aivatoglou said in a statement released by Tennis Australia.

"Most importantly, everything went smoothly and mother and daughter are well. Bec and Lleyton very much look forward to taking their daughter home in the coming days."

The pair are one of Australia's best-known celebrity couples.

Hewitt is a former Wimbledon and US Open champion while Cartwright was an actress in the Australian television soap opera "Home and Away".

Hewitt proposed to Cartwright after losing this year's Australian Open final to Russian Marat Safin following a whirlwind romance. They married in July.

Hewitt had been due to tie the knot with Belgian tennis player Kim Clijsters in February but she called the wedding off following a four-year relationship.

Cartwright was also involved in a long-term relationship before splitting with actor Beau Brady, late last year.

She was a regular fixture in the Hewitt family supporters box during the Australian Open but their sudden engagement and announcement they were expecting a child caught everyone by surprise.