10:56 CET - Eighth seed Matteo Berrettini has been dumped out in Hangzhou after the Italian fell to a 6-3, 6-3 defeat against lucky loser Dalibor Svrcina.
Meanwhile, in Chengdu, Taro Daniel and Dino Prizmic are safely through after straight-set wins.
10:49 CET - USA have booked their spot in the last four of the BJK Cup after Jessica Pegula and Taylor Townsend saw off Elena Rybakina and Yulia Putintseva 6-2, 7-6(1) in the decisive doubles rubber to complete a 2-1 victory over Kazakhstan.
They'll now face either Great Britain or Japan in the semi-finals over the weekend.
10:15 CET - Top seed Iga Swiatek is one set to the good in her opening match in Seoul, with the Pole leading Sorana Cirstea 6-3.
Follow the second set with Flashscore here.
Elsewhere, Lorenzo Sonego, Alejandro Tabilo and Tomas Martin Etcheverry have all claimed victories in China.
09:57 CET - Giovanni Mpetshi Perricard is through in Chengdu after recovering from a set down to defeat Filip Misolic 3-6, 6-1, 6-4, while Ekaterina Alexandrova and Suzan Lamens have advanced in Seoul.
09:53 CET - Kazakhstan have levelled their BJK Cup quarter-final against USA, with Elena Rybakina easing past Jessica Pegula in straight sets, 6-4, 6-1.
Follow the decisive doubles rubber here.
07:40 CET - Good morning and welcome to our coverage of today's tennis!
We've got a busy day of action to look forward to in Asia, as top seed Iga Swiatek begins her campaign in Seoul at 08:30 CET, while Emma Raducanu comes up against Barbora Krejcikova in an intriguing clash between two former Grand Slam champions.
Elsewhere, the remaining two quarter-finals at the BJK Cup are also taking place, with USA already 1-0 up on Kazakhstan and Great Britain facing Japan a little later.
Check out the full schedules in Chengdu, Hangzhou and Seoul via the links.