By Chrös McDougall | Jan. 15, 2019, 11:01 a.m. (ET)

Venus Williams celebrates winning her first-round match at the Australian Open on Jan. 15, 2019 in Melbourne.

 

Serena Williams might be seeded just 16th at the Australian Open, but the seven-time champ left no doubt that she means business as she swept past Germany’s Tatjana Maria 6-0, 6-2 in the tournament’s opening round on Monday.

The 37-year-old Williams is going for her record-tying 24th Grand Slam singles title, and her first since winning at Australia while eight weeks pregnant in 2017.

Williams, a four-time Olympic gold medalist who was the runner-up at Wimbledon and the US Open last year, was one of nine U.S. women and six U.S. men who advanced to the second round, which begins Tuesday night.

Joining Williams in the women’s round of 64 is her sister, Venus Williams, who mounted a huge comeback against 25th-ranked Lara Arruabarrena of Spain. Venus Williams, who is unranked, dropped the first set and then needed a tiebreaker to win the second set before pulling away in the third.

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Sloane Stephens, the top-ranked U.S. woman at No. 5, overcame fellow American Taylor Townsend in two sets, ending a stretch of three consecutive first-round exits in Australia. Madison Keys, who is ranked 17th, also advanced with a two-set sweep, beating Australia’s Destanee Aiava.

They are joined in the second round by 2014 Youth Olympian Sofia Kenin, Madison Brengle, Amanda Anisimova, Danielle Collins and Sachia Vickery. At least one American is guaranteed a spot in the third round, as Collins and Vickery are slated to meet on Court 13 tonight. Collins upset 14th-seeded Julia Goerges of Germany in the first round. Kenin has the challenge of facing top-ranked Simona Halep of Romania in the second round, with their match slated for Wednesday.

On the men’s side, the biggest shocker came when unseeded American Reilly Opelka upset fellow American John Isner in four sets on Sunday, with all four being decided in tiebreakers. Isner, at No. 9, was the highest seeded American man. Steve Johnson, the only other seeded American at No. 31, also fell in the first round.

2012 Olympian Ryan Harrison, Mackenzie McDonald, Taylor Fritz, Frances Tiafoe and Denis Kudla join Opelka in the final 64.

Tiafoe, who turns 21 next week and is the fourth-youngest player in the ATP Top 50, meets South Africa’s Kevin Anderson tonight on Margaret Court Arena. Anderson is seeded fifth. McDonald also faces a tough second-round matchup when he faces sixth-ranked Marin Cilic of Croatia tonight at Hisense Arena.

Competition has yet to get underway in doubles and mixed doubles. The event runs through Jan. 27 in Melbourne.

Chrös McDougall has covered the Olympic movement for TeamUSA.org since 2009 on behalf of Red Line Editorial, Inc. He is based in Minneapolis-St. Paul.