Four months ago Emma Raducanu shocked the tennis world by winning the US Open. Shocked might actually might be an understatement.

Raducanu, only 18 and ranked No.150, defeated Leylah Fernandez 6-4, 6-3 to complete a 10-match tear at the Billie Jean King National Tennis Center. She was the first qualifier to win a Grand Slam singles title and the first British woman in more than 40 years to take a major title.

Two days after that final, Raducanu joined Fernandez and Naomi Osaka at the Met Gala in New York. Raducanu won the BBC’s Sports Personality of the Year and was made a Member of the Order of the British Empire by Queen Elizabeth II.

How does the 19-year-old – now ranked No.19 – follow up that kind of blazing run so few ever experience? That’s the looming question heading into Monday’s Sydney Tennis Classic, a WTA 500 event that runs Jan. 10-15.

Sydney draw: Raducanu, Muguruza return to action in loaded field

Raducanu’s post-Open on-court record wasn’t spectacular. She was 2-3 to finish 2021, but a case of COVID-19 forced her to withdraw from an exhibition in Abu Dhabi and last week's Adelaide International. Some context: This will be the ninth WTA event of Raducanu’s career, and she’s working with a new coach, Torben Beltz.

What to expect this week? With a field featuring five of the WTA’s Top 10 players, now – according to former greats Martina Navratilova and Pam Shriver – would be a good time to temper any unrealistic expectations for Raducanu in 2022.

Photo by Jimmie48/WTA

“It’s going to be hard for her this year,” Navratilova said. “Players have seen her, they know what to do against her. But most of all, she just needs matches. She’s the biggest wildcard for me. Because clearly, she has the ability to play great tennis. Can she replicate it consistently enough?”

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Shriver added, “I think 2022 is going to continue to be a challenge for her. I think it’s going to be 2023 when we have a clearer idea of what her consistency level is going to be.”

This is only one of a handful of compelling storylines heading into Sydney:

Can Garbiñe Muguruza start the 2022 season as well as she finished 2021?

There’s no reason to believe she can’t.

In defeating Anett Kontaveit (twice) as well as Barbora Krejcikova and Paula Badosa at the WTA Finals in Guadalajara, Muguruza exhibited the fearless, predatory look we saw when she won the 2016 French Open and Wimbledon in 2017. The victory in Mexico marked her as one of the favorites to challenge Ashleigh Barty’s World No.1 ranking. Maybe the favorite.

“I’m just very happy I proved to myself once again I can be the best, I can be the `maestra,’ like how we say in Spanish,” Muguruza said afterward. “That puts me in a very good position for next year, a good ranking.

“The last couple of years, I didn’t play the same way I played before. But I didn’t play bad tennis, either. I was just here, there, not going into the deep rounds at Grand Slams that made the difference.”

And that will be a priority in 2022. There’s no question Muguruza likes Australia; she reached the final only two years ago, just before the global pandemic hit. Last year, she got to the Melbourne 500 final, losing a close one to Barty, and the fourth round at the Australian Open, falling to eventual champion Naomi Osaka 5-7 in the third.

Muguruza, seeded No.2 in Sydney, receives a bye and then the winner of Ekaterina Alexandrova and a qualifier.

Will Barbora Krejcikova back up her fabulous 2021?

Like the teenagers Raducanu and Fernandez, it will be difficult to duplicate her accomplishments of last season but, to be fair, Krejcikova’s 2021 had a broader bandwidth of consistently excellent results.

In June, she won the singles and doubles titles at Roland Garros and followed it up with a fourth-round appearance at Wimbledon and another title in Prague. She and Katerina Siniakova won the gold medal in Tokyo and there were singles quarterfinal appearances in Cincinnati and the US Open.

Unlike the other year-end qualifiers, Krejcikova elected to play the Billie Jean King Cup before heading to Guadalajara – where she was the only one to play singles and doubles. By the end, she appeared exhausted; Krejcikova lost all three of her round-robin matches before heading home to the Czech Republic.

Training in Dubai, she fell ill and had to suspend training. She was scheduled to play Adelaide but wasn’t ready. Sydney will be our first look at the No.5-ranked player. Based on her season-long success a year ago, expect more of the same.

How will Top 10 newcomers Anett Kontaveit and Paula Badosa fare a week before the Australian Open?

This is our first 2022 look at Kontaveit, while Badosa lost to Victoria Azarenka in a first-round match in Adelaide.

They both finished the 2021 season furiously, qualifying for the WTA Finals in Guadalajara. They both lost to Muguruza, Badosa in the semifinals and Kontaveit in the final.

Badosa began last season ranked No.70, but came through with her first career title at the Serbia Ladies Open and backed it up by reaching the quarterfinals at Roland Garros. The breakthrough came at Indian Wells, where she beat, in order, Coco Gauff, Krejcikova, Kerber, Ons Jabeur and Victoria Azarenka.

Kontaveit was ranked No.23 as 2021 opened, but didn’t truly catch fire until late. She won the titles in Cleveland, Ostrava, Moscow and Cluj-Napoca.

Both players are still relatively young by today’s tennis standards. Badosa, who turned 24 in November, is ranked No.8. Kontaveit, who celebrated her 26th birthday in December, is No.7. While they have a lot of points to defend, they should continue to produce good results this year.

In Sydney, Kontaveit opens with Zhang Shuai and Badosa plays Jelena Ostapenko.

What to expect from the unpredictable Ons Jabeur?

Like Kontaveit and Badosa, Jabeur soared into the Top 10 for the first time on a trajectory most of us didn’t see coming – sort of like some of the unconventional shots she hits on the court.

The season began quietly enough, but she won eight of 10 matches in two Charleston events and reached the fourth round at Roland Garros. Moving to grass, she won the first title of her career in Birmingham, then made the Wimbledon quarterfinals, beating Venus Williams, Muguruza and Swiatek in the process.

Jabeur has a wonderfully diverse game and a playful sense of humor that should keep her grounded. The first-round opponent in Sydney is wildcard Astra Sharma, with a potential matchup against Petra Kvitova in the second.