By Karen Price | Jan. 21, 2019, 10 a.m. (ET)

Danielle Collins competes at the Australian Open on Jan. 20, 2019 in Melbourne.

 

Four-time Olympic gold medalist Serena Williams got one step closer closer to another Grand Slam final, unseeded American Danielle Collins knocked off the No. 2 seed to keep her surprising run alive and Frances Tiafoe continued to turn heads in Round of 16 action at the Australian Open. 

In one of the prime clashes of the round, Williams took down top seed Simona Halep of Romania in three sets, 6-1, 4-6, 6-4. After blazing through the first set, Williams had a tougher time in the second as the No. 1 women’s player in the world succeeded in finding a groove and getting Williams out of hers. Then in the third set both players had their chances, but Williams got break point in the seventh game to break a 3-3 tie then held serve both games for the win. 

This was their 10th meeting and their first since Williams won a 134-minute three-set battle at the 2016 US Open. Williams has now won nine matches against Halep, who defeated Venus Williams in the round of 32. 

She’ll now face Czech Karolina Pliskova, who defeated two-time Grand Slam champion Garbine Muguruza of Spain, in the quarterfinal. Williams won her most recent Grand Slam title while pregnant playing at the Australian Open in 2017 before taking time off from the game. 

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Meanwhile, Collins sailed past second-seeded Angelique Kerber, 6-0, 6-2, and is the only remaining U.S. woman besides Williams in the singles tournament. The 25-year-old two-time NCAA champion from Virginia had never won a Grand Slam match prior to this week and had never beaten a top-five opponent before dispatching Kerber with ease. Collins, who turned pro in 2016, will next face Russia’s Anastasia Pavlyuchenkova, who defeated Sloane Stephens in the quarterfinals. 

On the men’s side, only Tiafoe remains among the Americans who started the tournament. He won’t soon forget his 21st birthday, either, as the unseeded American spent it beating No. 20 Grigor Dimitrov of Belarus to reach his first Grand Slam quarterfinal, 7-5, 7-6, 6-7, 7-5. The crowd even sang happy birthday after Tiafoe had to come from behind and win five points in a row to take the second set, then breaking Dimitrov in the 11th game of the fourth set for the win. 

His next challenge will be 17-time Grand Slam champion Rafael Nadal in the quarterfinals. 

In men’s doubles, Ryan Harrison and Sam Querrey defeated Americans Jack Sock and Jackson Withrow, 4-6, 6-3, 7-5, while the newly-reunited twin duo of Bob Bryan and Mike Bryan topped Spaniards Pablo Careno Busta and Guillermo Garcia Lopez, 6-3, 7-6 (4). This is their first tournament back together since Bob Bryan’s hip surgery last year, when Mike Bryan continued on in a successful partnership with Sock as his teammate. They are looking for their 17th Grand Slam trophy. In women’s doubles, Alison Riske and Jennifer Brady moved into the quarterfinals with a 6-3, 6-4 win over Nicole Melichar and Czech Kveta Peschke.

Action continues Monday in Melbourne. The tournament concludes Jan. 27.

Karen Price is a reporter from Pittsburgh who has covered Olympic sports for various publications. She is a freelance contributor to TeamUSA.org on behalf of Red Line Editorial, Inc.