MELBOURNE, Australia (AP) — The Latest on Friday at the Australian Open (all times local):
Play is finally underway on the outdoor courts at Melbourne Park — about 2 1/2 hours late because of heavy morning rain.
While play began on time at the three main show courts — Roger Federer, Ashleigh Barty and Stafanos Tsitsipas were early winners there— the rain left many of the outdoor courts flooded with water.
Skies were still cloudy and a threat of rain remained through the afternoon.
Federer ensured his 100th Australian Open match was over quickly, and raised his racket to acknowledge the Rod Laver Arena crowd.
The six-time champion conceded only three points on his first serve in a 6-2, 7-5, 6-2 win over 21-year-old American Taylor Fritz, who was bidding to reach the fourth round at a major for the first time.
Federer is into the Round of 16 at a Grand Slam event for the 63rd time.
"I think I wanted to get out of the blocks quickly. I knew of the threat of Taylor," Federer said. "I think I had extra focus today."
He will next play Stefanos Tsitsipas, who had a 6-3, 3-6, 7-6 (7), 6-4 win over Nikoloz Basilashvili to become the first Greek man to reach the fourth round at multiple majors.
Stefanos Tsitsipas is through to the fourth round at Melbourne Park with a 6-3, 3-6, 7-6 (7), 6-4 win over Nikoloz Basilashvili.
Tsitsipas broke the Georgian player's serve to take a 4-3 lead, then had a match point on Basilashvili's serve at 5-3. He served out the match in the next game, winning when Basilashvili hit a forehand into the net.
Tsitsipas is the first Greek man to reach the round of 16 at two tennis majors. Next he will face either defending champion Roger Federer or American Taylor Fritz.
Tsitsipas received a warning for unsportsmanlike conduct from chair umpire Alexandra Robein when he became angry after having his service broken while serving for the third set at 5-4. While serving for the first set, he had to stop because of a screaming infant in the Margaret Court Arena crowd.
Rain and wet courts continued to delay the start of play on all the outside courts. Play went ahead on the three main show courts with the stadium roofs closed.
Local favorite Ashleigh Barty has become the first player through to the fourth round at Melbourne Park with a 7-5, 6-1 win over Maria Sakkari at Rod Laver Arena.
Barty received treatment for an apparent stomach muscle ailment at the end of the first set but appeared not to be affected for the rest of the 82-minute match.
Barty will play either Maria Sharapova or defending champion Caroline Wozniacki in the next round. They play their third-round match later Friday at Rod Laver Arena, with defending men's champion Roger Federer's match against American Taylor Fritz in between.
Rain forced a continuing delay to the start of matches on outside courts. The roofs on all three main arenas were closed.
Greek stars Stefanos Tsitsipas and Maria Sakkari featured on two of the three main show courts at Melbourne Park as rain delayed the start of play on outside courts.
It's the first time a Greek man and woman have advanced to the third round at the same Grand Slam tournament since 1936.
At Rod Laver Arena, Sakkari lost the first set to Ashleigh Barty 7-5 and the Australian received treatment for an apparent stomach muscle issue at the end of the first set. A group of young men in blue t-shirts were vocal supporters of Sakkari, chanting Greek songs that echoed around the closed-roof arena.
Over at adjoining Margaret Court Arena, Tsitsipas took the opening set 6-3 against Nikoloz Basilashvili but the Georgian player won the second by the same score.
Tsitsipas was having to deal with an inconsistent ball toss, a bird trapped inside the arena that frequently swooped low over the court and a chair umpire that mispronounced his name.
One Greek fan frequently began a slow clap just before Tsitsipas' serves and yelled "go go go." With the Greek player trailing 3-0 in the second set, moral support appeared to be on the way: Patrick Mouratoglou, Serena Williams' coach, came down the stairs and headed to his player's box. Tsitsipas trains at the Mouratoglou Academy in France.
Caroline Wozniacki will have her most daunting challenge in defense of her Australian Open women's singles title when she takes on five-time Grand Slam champion Maria Sharapova in the third round at Melbourne Park on Friday.
The two haven't played since 2015 when Sharapova finished the year ranked fourth and Wozniacki was 17th. Now Wozniacki is seeded third here and Sharapova is 30th.
The match preceding that one on Rod Laver Arena will see defending men's singles champion Roger Federer take on American Fritz Taylor. Rafael Nadal opens night play on the same court against Australian Alex de Minaur, followed by 2016 champion Angelique Kerber's match against Australian wild-card entry Kimberly Birrell.
Morning rain showers meant the roofs at all three main show courts were closed and the start of play was delayed on outside courts.
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