After three months on hard courts, the 2021 clay season is under way.
The men are competing in Cagliari and Marbella this week, while the women are in action in Charleston and Bogota. The first Masters 1000 clay event of the season then takes place in Monte Carlo from April 11.
With everything building up to Roland-Garros, which will now start with the main draw on May 30 after it had to be postponed, who are the players that need some big results ahead of the second Grand Slam of the year?
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Dominic Thiem

It has been a difficult start to the year for Thiem, who won his first Grand Slam title seven months ago at the US Open.
The world No 4 lost in the fourth round of the Australian Open before early exits in Doha and Dubai. He has also confirmed he will not play in Monte Carlo and has some "tough weeks ahead" as he looks to get back to full fitness.
Thiem, whose preferred surface is clay, has been battling a foot injury, but there also appears more to his dip in form than that.
Speaking last week he admitted he is still processing his US Open win. "It's such a big thing to realise your career goal. In the beginning, I didn't realise how much it took out of me, in a way it still does. Dealing with it, digesting it, it’s a process I still have to learn."
With the extended ranking system, Thiem has plenty of points against his name over the clay season. He is still holding points from reaching the final of Roland-Garros in 2019, as well as reaching the semi-finals in Madrid and winning Barcelona. If he doesn’t return to form soon then he is likely to slip down the rankings.

Sloane Stephens

Former French Open finalist Stephens has had a tough few years.
She has fallen from No 6 in the world in 2018 down to No 57, with victories proving hard to come by. Last year she managed just four wins on the WTA Tour, and her win over qualifier Oceane Dodin at last week’s Miami Open was her first of 2021.
But could a return to clay spark a turnaround for Stephens?

Sloane Stephens

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After making the final at Roland-Garros in 2018 – losing to Simona Halep – she made the quarter-finals in Charleston in 2019, followed by the semi-finals in Madrid and last eight in Paris. She is hopeful that her results will start to improve soon.
"Tennis is a very quick turnaround sport," she said ahead of playing in Charleston. "You could be having the worst season of your life and then go win the French Open or win a Premier 5 and everything is back to normal. I think for myself, being realistic and knowing where I am in my game, what I need to work on, and where I want to improve, that takes time.
"Obviously, no one stays in a rut for the rest of their life, or the rest of their career. It's just literally not possible. At some point, the tables do turn, the tides turn, and you just kind of have to be ready for when that does happen."

Iga Swiatek

Swiatek doesn’t need a big clay season like Stephens or Thiem, but it will be intriguing to see if, after her shock win at the French Open last year, she can deliver on a consistent basis over the next six weeks.
She’s already got a tournament win to her name in 2021 after victory at the Adelaide International and is looking forward to the chance of getting back to her favourite surface.

Iga Światek z trofeum French Open

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"I feel comfortable and love playing on clay," she said after losing in the third round of the Miami Open. "I can't wait for my clay court time to come again. The clay start last year was not good for me, because I lost in the first round in Rome. Then it all ended in the best way, winning Roland Garros. I will enjoy every game and every tournament."
Swiatek could be one of the players to beat on the clay. During her ITF and WTA careers she owns a 62-11 record on the surface and won the French Open last year without dropping a set.

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Rafael Nadal

This is a fascinating period for Nadal.
He hasn’t played since losing in the quarter-finals of the Australian Open to Stefanos Tsitsipas and has been recovering from a back injury. He is set to return to action in Monte Carlo and has been "training well and training hard" according to his doctor, Angel Ruiz Cotorro.
Since the last time he played, Nadal has slipped down a place in the rankings to No 3 in the world, with Daniil Medvedev moving up to No 2. It has been four years since Nadal was any lower, but he has plenty of points to defend over the next few months, which could prove tricky if he is still not at full fitness.
In questioning whether Nadal will dominate on clay again it feels almost inevitable that he probably will, but he does at least appear vulnerable heading on to the dirt in 2021.

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Sofia Kenin

Kenin had a superb 2020, starting it by winning her first Grand Slam title at the Australian Open and then reaching the final of the French Open.
But, ranked fourth in the world, she has not had the best start to 2021, suffering a tearful second-round exit in Melbourne and then losing early at the Phillip Island Trophy and Miami Open.
She could be one to watch if she can rediscover her best form on clay. She admits she used to "hate" playing on the surface as a junior, but has shown she has adapted to it over the last few years.
With so much competition at the top of the women’s game, it would be great to see Kenin challenge as well over the next few months.
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