United Cup 2027 groups confirmed as Coco Gauff, Holger Rune and Emma Raducanu headline star-studded field

The United Cup 2027 is beginning to take shape, with 18 nations set to compete across Perth and Sydney from January 1-10. Several of the sport's biggest names have already committed to the mixed-team competition, including Coco Gauff, Ben Shelton, Holger Rune, Emma Raducanu, Felix Auger-Aliassime and Linda Noskova, with the group stage offering several intriguing matchups ahead of the Australian Open.

The fifth edition of the tournament will once again bring together established stars and emerging talents, with Denmark set to make its debut. Defending champions Poland will also return as they look to retain their title after securing their first trophy earlier this year, although they will have to do so without Iga Swiatek, one of the competition's most notable absentees.

The competition will feature six groups of three countries, with each city hosting nine nations. Every tie consists of one men's singles match, one women's singles match and a mixed doubles encounter, with two points needed to secure an overall victory.

The six group winners will advance to the quarter-finals, alongside the best runner-up from Perth and the best runner-up from Sydney. This means eight countries will remain in contention, with the semi-finals and final taking place in Sydney on January 9 and 10.

Perth will welcome several major names across its three groups, with world-class talent spread throughout the draw. Former world No. 4 Holger Rune will lead Denmark on its United Cup debut, while Felix Auger-Aliassime and rising star Victoria Mboko headline Canada's challenge. Defending champions Poland will also be in action, with Hubert Hurkacz and Maja Chwalinska looking to guide their country to back-to-back titles, while Coco Gauff and Ben Shelton will spearhead the United States.

Group C immediately stands out as one of the most attractive combinations, with Canada, Italy and Denmark bringing together several leading singles players. Rune could face Auger-Aliassime in a particularly compelling men's singles contest, while Mboko and Clara Tauson would provide another exciting potential matchup. Italy will also have Flavio Cobolli and Elisabetta Cocciaretto, adding further quality to an extremely competitive group.

Group A will feature Gauff and Shelton representing the United States, with Croatia relying on Donna Vekic and Dino Prizmic. The American pairing will face a potentially difficult challenge, particularly with Vekic capable of producing a strong performance against Gauff and Prizmic offering an interesting test for Shelton.

The defending champions will be in Group E, where Poland will attempt to continue its recent success without Iga Swiatek. Hurkacz and Chwalinska will lead the team against Germany and Switzerland, with Belinda Bencic providing one of the biggest challenges. A Chwalinska-Bencic encounter is particularly interesting, while Germany will count on Yannick Hanfmann and Tamara Korpatsch.

Sydney will host the remaining nine nations, divided into Groups B, D and F. The 2026 Wimbledon champion Linda Noskova and former US Open champion Emma Raducanu are among the biggest names competing in the city. Former top-three players Maria Sakkari and Stefanos Tsitsipas will also return to the event, while Paula Badosa will form an intriguing partnership with youngstar Rafael Jodar.

Group B could produce one of the most attractive matchups of the opening stage, with Noskova and Jiri Lehecka leading Czechia against Greece's Tsitsipas and Sakkari. The potential women's singles clash between Noskova and Sakkari stands out, while Lehecka and Tsitsipas could also provide a high-quality men's contest. Hungary completes the group, with Fabian Marozsan and Panna Udvardy among its representatives.

France will be another team worth following in Group D, with Arthur Fils and Diane Parry among its leading players. They will face Australia and Great Britain, creating several interesting possibilities. Fils could meet home favourite Rinky Hijikata, while Raducanu will be one of the main attractions for the British team alongside Arthur Fery and Neal Skupski. Australia will also have Talia Gibson and Rinky Hijikata, with the women's singles encounter between Gibson and Raducanu potentially drawing considerable attention.

Group F features Belgium, Spain and Argentina. Badosa and Jodar will form an interesting combination for Spain, while Belgium can count on Elise Mertens and Alexander Blockx. Argentina will also bring competitive singles options, with Tomas Martin Etcheverry and Solana Sierra among its representatives.

Poland will arrive in Australia as the reigning champions after securing its first United Cup title in 2026. The team defeated Switzerland 2-1 in the final, completing an impressive campaign that included victories over Australia and the United States in the knockout rounds.

Hurkacz and Chwalinska will now have the task of defending that achievement, although the team will have a different composition without its biggest star.

Swiatek will be one of the most notable absentees after choosing the Brisbane International to begin her 2027 campaign instead. This will mark the first time she skips the United Cup, having participated in every edition since the competition was introduced in 2023. Her absence is particularly significant given her contribution to Poland's breakthrough title earlier this year.

Zverev will also miss the competition after opting for Brisbane, where he is expected to begin his new season. The German has been a familiar presence at the United Cup in previous years, making his decision another notable change to the tournament's lineup.

Nevertheless, the field remains packed with established names and emerging talents, with 12 top-20 players from the ATP and WTA rankings listed among the participants. With Denmark making its debut, Poland attempting to defend its crown and several intriguing matchups across both cities, the United Cup will once again provide an important opening to the Australian tennis summer.