Kerber, Thiem to compete in Sydney

World No.1 Angelique Kerber will play next year's Sydney International for the fifth-straight year as she prepares her Australian Open title defence.

The German will step onto Ken Rosewall Arena in January a week after kicking off the year at the Brisbane International.

Kerber has never won the Sydney tournament. She was a finalist in 2014 , and this year lost her semi-final to Karolina Pliskova.

Austrian world No.10 Dominic Thiem will also back up from Brisbane to compete in Sydney, while retired Australian champion Lleyton Hewitt has been confirmed for a legends match.