MELBOURNE, Australia (AP) — The Latest from the Australian Open on Monday (all times local):

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11 a.m.

Some said it wouldn’t happen amid the COVID-19 pandemic. Some said it shouldn’t happen. Well, the 2021 Australian Open is officially underway.

Naomi Osaka opens play at Rod Laver Arena when she takes on 39th-ranked Anastasia Pavlyuchenkova, a quarterfinalist three of the past four years in Melbourne.

Serena Williams begins her latest bid for a 24th Grand Slam singles title in the following match against Laura Siegemund. Serena's older sister Venus, a seven-time major champion, is first up at Margaret Court Arena against Kirsten Flipkens.

They are among eight women Grand Slam singles titlists playing on the opening day. Others include two-time Wimbledon champion Petra Kvitova and 2019 U.S. Open winner Bianca Andreescu. There were six tuneup tournaments crammed into last week, with top-ranked Ash Barty among the winners of the five finals staged on Sunday.

The tournament is beginning three weeks later than scheduled because of cororavirus quarantine requirements for the players. It started under mostly cloudy skies and a temperature of 17 Celsius (63 Fahrenheit)

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