Four Grand Slam champions -- Iga Swiatek, Angelique Kerber, Aryna Sabalenka and Emma Raducanu -- have been announced for the field of the 2024 Porsche Tennis Grand Prix in Stuttgart, which begins on April 15.

Two of the quartet are also multiple former titlists at the event. World No.1 Swiatek is the two-time defending champion, having claimed the title in 2022 and 2023. Former World No.1 and home favorite Kerber was a back-to-back winner in 2015 and 2016. The pair faced off for the second time in the United Cup final this week, with Swiatek winning 6-3, 6-0.

Sabalenka also has a strong historic record in Stuttgart, having reached the final for the past three years in a row. However, the World No.2 has yet to lift the trophy -- or win the Porsche car that comes with it. She fell to Ashleigh Barty in 2021, and Swiatek in both 2022 and 2023.

Raducanu will be making her third appearance at the tournament, where she reached her first tour-level clay-court quarterfinal in 2022. Stuttgart was the Briton's last outing in 2023 before she shut her season down to undergo multiple wrist and ankle surgeries. Raducanu returned from her eight-month layoff this week in Auckland, reaching the second round.

Kerber will also be continuing her comeback season in Stuttgart. Like Raducanu, the German returned to action this week, helping Germany win its first United Cup title alongside fellow former Stuttgart champion Laura Siegemund. Kerber, who gave birth to daughter Liana last February, claimed the first win of her return from maternity leave against Ajla Tomljanovic in the United Cup semifinals.

The tournament is one of the longest-standing stops on the Hologic WTA Tour. It was first held in Filderstadt in 1978, moving to Stuttgart in 2006. It has been a spring indoor clay event since 2009, and former champions of its current incarnation include Justine Henin, Maria Sharapova, Petra Kvitova and Svetlana Kuznetsova.

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