Williams advances to Auckland WTA semis

Ben McKay
Serena Williams has advanced in straight sets to the semi-finals of the ASB Classic in Auckland

Serena Williams has surged into the semi-finals of Auckland's Australian Open lead-up event after beating Laura Siegemund in straight sets.

The 23-time major winner bludgeoned her way to a 6-4 6-3 success in one hour and 27 minutes on Friday at the ASB Classic.

While troubled by some spectacular backhand winners by Siegemund and blustery conditions, Williams still smacked 26 winners including six aces.

"I am definitely not super comfortable. I am trying. I would do a little bit better if I wasn't hitting every shot in a conundra of wind," Williams said.

"I got a little negative in the end. It was just so windy.

"It was good for me to fight ... she stepped up and hit a lot of good winners. It was not easy. I had to step up and play a little better and get through it."

The win ensures Williams' best tournament before Melbourne Park in more than a decade, given the legendary American usually skips ranked lead-up events.

She will face fellow American Amanda Anisimova on Saturday afternoon for a place in the final, after the teenage talent defeated Eugenie Bouchard 6-2 3-6 6-4 in Friday's late quarter final.

Williams opted for New Zealand to prepare for her 19th Australian Open campaign, where she aims to tie Margaret Court's mark of 24 grand slam titles.

In the first set in Auckland, the 38-year-old had the German's measure without forcing a break until the final game.

Williams was broken early in the second set as she struggled in the wind, misreading the ball in flight several times and throwing her hands to the sky in frustration.

Trailing 0-40 on serve, Williams won five straight points in a ferocious comeback and completing the return break with the help of a net cord.

Pushing Siegemund to all corners of the court, Williams then raced through the final five games of the set to close out the match.

Retiring star Caroline Wozniacki, who is partnering with Williams in the Auckland doubles, also won through to the last four by defeating Julia Goerges.

The Dane, who is leaving the game to start a family after the Australian Open, defeated the two-time defending Auckland champion 6-1 6-4 in 75 minutes.

Wozniacki will play American Jessica Pegula in their semi-final.

Pegula, a New York state native, ousted Alize Cornet 6-0 3-2 when the struggling Frenchwoman retired complaining of an upper right thigh issue.

The 25-year-old will make her Australian Open debut in a week's time after a breakthrough 2019 which included her first WTA title in Washington.