MELBOURNE, Australia (AP) — The Latest on Tuesday at the Australian Open (all times local):
Two-time champion Victoria Azarenka's return to the Australian Open for the first time since 2016 has ended in a first-round loss to Laura Siegemund.
Azarenka, who won back-to-back Australian Open titles 2012 and '13, lost 6-7 (5), 6-4, 6-2 to the No. 110-ranked Siegemund.
The first set was delicately poised in the tiebreaker when Azarenka took control, but Siegemund said she "took time out and I reset myself" in the break and regained control of the match. She broke the 29-year-old Azarenka's serve seven times, including three times in the last set.
The former No. 1-ranked Azarenka took time out of the game after birth of her son, Leo, in December 2016 and reached the round of 16 at Wimbledon in 2017 but did not play any further tournaments in the season after taking time out again for personal reasons.
After skipping last year's Australian Open, she steadily improved at the majors after a first-round exit at the French Open, a second-round loss at Wimbledon and a third-round appearance at the U.S. Open and moved to to No. 53 in the rankings.
Tenth-seeded Daria Kasatkina has lost 6-3, 6-0 in the first round of the Australian Open to Timea Bacsinszky.
Kasatkina, who reached the quarterfinals at the French Open and Wimbledon and broke into the top 10 last October after winning a title in Moscow, struggled with her serve and had nine double-faults in the 55-minute defeat.
It was the third consecutive tournament in Australia where Kasatkina lost in the first round following her early exits at the Brisbane International and the Sydney International.
Fourth-seeded Alexander Zverev broke Aljax Bedene's serve in the seventh game of the third set and went on to complete a 6-4, 6-1, 6-4 win over the Slovenian player to reach the second round at Melbourne Park.
Zverev finished last year strongly, winning the ATP Finals with victories over Roger Federer in the semifinals and Novak Djokovic in the final. At 21, he became the youngest winner of the event since Djokovic in 2008 and the first German champion since Boris Becker in 1995.
Zverev, who also won three other tournaments in 2018, hasn't advanced beyond the third round in three previous trips to the Australian Open.
Serena Williams has her own name for the green one-piece suit she wore in her first-round win at the Australian Open.
She was asked to describe it, for the sake of any fashion-challenged fans. It's not a onesie, it's not a leotard, the question went, so what is it?
"It's a Serena-tard," the 23-time major winner said, laughing at her own description of yet another fashion statement.
What it was, Williams explained, was a show of strength: "An incredibly strong, powerful statement for moms that are trying to get back and get fit. That was basically it for me."
The 37-year-old Williams was back at the Australian Open for the first time since 2017, when she won the title while pregnant. She took time out from the tour and is now into her fourth Grand Slam tournament since returning.
Williams developed blood clots after giving birth to daughter Alexis Olympia Ohanian Jr. on Sept. 1, 2017, and had four surgeries. She returned to the WTA Tour last March and played in two events before the French Open, where she competed in a skin-tight, full-length black catsuit.
She said at the time the outfit — worn partly for health reasons because of the clots — made her feel like a superhero.
Compression stockings have remained part of her ensemble, Williams said, as a precaution because she still has concerns about deep vein thrombosis.
"I have had some issues, and they're not done. So it's just something I just have to do for pretty much probably the rest of my career," she said. "With DVT, it's very scary ... for me it's incredibly frightening."
Eugenie Bouchard advanced to the second round at Melbourne Park with a 6-2, 6-1 win over wild-card entry Peng Shuai.
Peng saved one match point on her serve but a backhand wide gave the Canadian another, and Bouchard clinched the 59-minute match with a forehand to the open court.
The 2014 Wimbledon finalist's ranking dropped from a career-high of five to a current 79 to start 2019 after a series of injuries and poor form.
Bouchard, who also made the Australian Open and French Open semifinals in a breakthrough 2014, will be severely tested in her second-round match Thursday when she plays 23-time Grand Slam singles champion Serena Williams.
Kei Nishikori rallied from two sets down and won 10 consecutive games before Kamil Majchrzak retired with the score at 3-6, 6-7 (6), 6-0, 6-2, 3-0 at Margaret Court Arena.
Nishikori had a chance to win the second set, up 30-0 on the Polish player's serve at 5-4. But he let Majchrzak back into the game and when the set went to a tiebreaker, two unforced errors by Nishikori handed his opponent the set.
Those mistakes riled Nishikori between the second and third sets, obviously upset with himself as he placed ice cubes in a plastic bag on the back of his neck.
He came out firing to start the third set and his 10-game streak and 15 of the last 17 before Majchrzak had enough and stopped the match.___
Serena Williams was relentless in her first appearance at Melbourne Park since winning the title in 2017, losing only five points in the opening set on her way to a 6-0, 6-2 win over Tatjana Maria in just 49 minutes.
The 23-time major winner didn't defend her title last year while she was taking time off following the birth of her daughter.
Maria wasn't helped by her woeful serving — she made only three of 14 first serves in the opening set.
Williams gave Maria, who also has a daughter, a warm embrace at the end of the match.
The 16th-seeded Williams will face either Eugenie Bouchard or wild-card entry Peng Shuai in the second round.
An Australian Open line judge was taken from the court for several minutes after being hit by a ball during a first-round men's singles match between Fabio Fognini and Jaume Munar.
After being hit in the lower back by a serve from Munar, the woman was checked by medical officials and returned to continue officiating on the baseline of the match at one of Melbourne Park's minor show courts.
After Munar apologized, the match was halted for several minutes. A replacement official took over briefly before the line judge returned, receiving loud applause from the crowd.
Former U.S. Open finalist Madison Keys beat Australian wild-card entry Destanee Aiava 6-2, 6-2 to open play at Rod Laver Arena on Day 2 of the Australian Open.
Keys broke Aiava's serve in the third game of the second set to go up 2-1, then again in the seventh game thanks in part to an Aiava double-fault and two forehand errors.
Keys' best result at Melbourne Park was in 2015 when she beat Venus Williams and Petra Kvitova en route to the semifinals, where she lost to Serena Williams. She also made the quarterfinals last year, losing to 2016 champion Angelique Kerber.
The now 18-year-old Aiava had the distinction of being the first male or female player born in this century to play in a main draw Grand Slam singles match when she received a wild card in 2017. She lost in the first round.
Another early winner Tuesday was seventh-seeded Karolina Pliskova, who beat Czech qualifier Karolina Muchova 6-3, 6-2.
Novak Djokovic and Serena Williams, with 13 Australian Open titles between them, play their first-round matches Tuesday at what is expected to be a steamy Melbourne Park.
Williams, who has seven Australian titles and last won here in 2017, plays Tatjana Maria in the second match at Rod Laver Arena.
Top-seeded Djokovic, who will attempt to win a men's record seventh Australian title, opens night play on the same court against American Mitchell Krueger.
The temperature was already 30 degrees Celsius (86 Fahrenheit) when play began on all courts shortly after 11 a.m. local time and it was expected to rise by several degrees.
The sun and humidity added to the sultry conditions, forcing many of the early spectators to take relief by standing under giant cooling mist machines.
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