Angelique Kerber and Victoria Azarenka were warming up for their quarterfinal match at the Australian Open on Wednesday when, in a media interview room underneath Rod Laver Arena, the action that has attracted unwanted attention at this year's tournament had already begun.

The first Grand Slam of the year has been overshadowed from the start by BBC and BuzzFeed News reports alleging that match-fixing was widespread at the top level of the sport and that authorities had failed to thoroughly investigate evidence of corruption involving 16 players who have ranked in the top 50 over the past decade. No players were named in the reports.

On Wednesday, a half-hour before Kerber began her 6-3, 7-5 win over Azarenka to advance to the semifinals, tennis' governing bodies announced they will commission an independent review of their anti-corruption unit to restore "public confidence in our sport" following the reports that possible evidence of match-fixing was not properly investigated.

In announcing the review, ATP Chairman Chris Kermode said the reports had "caused damage to the sport," which compelled the major stakeholders in tennis — the International Tennis Federation, ATP and WTA tours, and the four Grand Slams — to take quick action to address the issue.

The independent review, earlier reported by The Associated Press, will be funded by the Tennis Integrity Board, which oversees the anti-corruption unit set up by the sport in 2008 to combat match-fixing, and led by Adam Smith, a London-based lawyer who is an expert in sports law.

Kermode acknowledged that Wednesday's announcement helped keep the topic of match-fixing prominent in and around the tournament action.

"It has been hard on the Australian Open, no question about it," Kermode said. "Obviously the report was timed to hit at this point, try to create as big a story as possible. But they've been unbelievably supportive of the actions we've taken. They agree we had to hit this head-on now even though it was during the championships."

Philip Brook, the chairman of Wimbledon and of the Tennis Integrity Board, said the early action "demonstrates to all of us how seriously we take this."

Back on the courts, Kerber won five consecutive games in the second set and saved five set points before beating two-time champion Azarenka. Kerber broke Azarenka's serve to end the match, beating the Belarussian for the first time in seven career matches.

The No.7-seeded Kerber will play the winner of the later quarterfinal between Johanna Konta of Britain and Chinese qualifier Zhang Shuai.

The other semifinalists — six-time champion Serena Williams and Agnieszka Radwanska — were determined on Tuesday. Both semifinals will be played Thursday, with the final on Saturday.

Two men's quarterfinals were scheduled for later Wednesday — No. 2 Andy Murray plays David Ferrer and Gael Monfils takes on Milos Raonic.