The 2021 WTA Tour season resumed as the inaugural Yarra Valley Classic got underway with 16 first-round matches.

Among the winners were Venus Williams, 13th seed Danielle Collins and 16th seed Marie Bouzkova. 12th seed Fiona Ferro and 15th seed Kristina Mladenovic were the seeds that were upset.

Venus, Collins, Bouzkova ease into second round

Williams looked dominant in a 6-1, 6-3 victory over Arantxa Rus, never dropping serve while hitting 18 winners to set up a blockbuster second-round clash against eighth seed Petra Kvitova.

"It's awesome to be back, I love Australia, it's a beautiful moment", she said following the match. "It's so hard to play the first match of the season, and I just think that maybe I just handled the nerves a little bit better.

"It's not easy. Of course, I have a lot of experience, and I think that helps. Just trying to get my feet wet, trying to compete here, and feel good about what i'm doing."

Collins, making her season debut, required just 75 minutes to see off qualifier Ysaline Bonaventure 6-3, 6-3. The American broke the Belgian twice in each set to reach the second round, where she next faces Nina Stojanovic.

Bouzkova saw off home favorite Samantha Stosur 6-2, 6-0, breaking the Aussie five times as Stosur was returning to the tour after giving birth during the COVID-19 break. The Czech won the final ten games of the match from 2-2 in the first set.

Rogers, Pegula pull off upsets of seeded French players

Shelby Rogers secured her second round berth with a 6-2, 7-5 win over Ferro. The American won 16 of the first 17 points of the match in racing out to a 4-0 lead and rallied from 5-1 down, claiming the final six games to move on.

Mladenovic suffered the same fate as her compatriot, albeit in much less dramatic fashion as Jessica Pegula as the American swiftly moved past the 15th seed 6-4, 6-1 where she will next play Germany's Mona Barthel.

Pironkova, Sevastova lead list of other winners

Among the other victors were Tsvetana Pironkova, who blasted Liudmila Samsonova 6-2, 6-1, Anastasija Sevastova, a 6-4, 6-2 winner over Madison Brengle, Ana Bogdan, cruising past Kamilla Rakhimova 6-2, 6-2, Aliona Bolsova, a 6-3, 6-0 winner over Akita Raina.

Also advancing were Stojanovic, who got past Mayar Sherif 6-3, 6-2, Barthel, who defeated Kimberly Birrell 7-5, 6-3, Rebecca Peterson, who routed Aussie wild card Maddison Inglis 6-2, 6-1 and Daria Gavrilova, who crushed Viktoria Kuzmova 6-2, 6-0.

Finally, three-set winners were Vera Lapko, who fought past Yaroslava Shvedova 4-6, 6-2, 6-4, Varvara Gracheva, rallying to defeat Lizette Cabrera 2-6, 6-4, 6-2 and Elisabetta Cocciaretto, who edged Lin Zhu 0-6, 6-3, 7-5.