The head-to-head between Naomi Osaka and Anastasija Sevastova is all square at 1-1, with both meetings so far coming on hard courts. The Japanese player took their first encounter 6-3, 6-4 in the second round of Toronto in 2017, but Sevastova gained her revenge this year 6-4, 6-1 in the second round of Doha.
All four of No.2 seed Caroline Wozniacki's matches against wildcard Wang Qiang have been played on Asian hard courts - and two here in Beijing. In their very first meeting, Wang saved a match point to upset the Dane 2-6, 7-6(1), 6-1 in the first round of Kuala Lumpur in 2013; it was the Chinese player's first career Top 10 win out of four so far - with the next three all coming this year. Since that match, Wozniacki has beaten Wang twice in straight sets - in the second round of Beijing in 2015 and the 2016 Hong Kong quarterfinals - and once over three sets, 6-1, 6-7(4), 6-1 in the first round here last year.
Naomi Osaka, fresh off a title run at the US Open and a runner-up place in Tokyo, is bidding to become the first player this season to reach three consecutive finals.
Wang Qiang is the first home player to reach the semifinals in Beijing since Li Na in 2012. The wildcard has won 17 of her last 20 matches, and 17 of her last 18 on home soil - with her only loss in China since January being her retirement against Anett Kontaveit in last week's Wuhan semifinals.
Both Naomi Osaka and Anastasija Sevastova are competing in their third semifinal at Premier Mandatory level or higher. In both of Osaka's prior two - Indian Wells and the US Open this year - the 20-year-old went on to lift the trophy. Sevastova, on the other hand, is yet to win a semifinal match at this level, having fallen to Simona Halep in Madrid last year and Serena Williams at the US Open this year.
Caroline Wozniacki broke a three-month streak of six tournaments in which she failed to win consecutive matches this week, and is now playing her first semifinal since Eastbourne in June. The Dane is also back in the Beijing semifinals for the first time since her title run here in 2010.
The best Premier Mandatory performance of Anastasija Sevastova's first career came here in Beijing when she reached the 2010 quarterfinals. Between that year and this, the Latvian had not won a match here, falling in the first round to Johanna Konta in 2016 and Maria Sharapova in 2017. Before this year, Naomi Osaka had not won a match in Beijing either, losing in the first round of qualifying to Tatjana Maria in 2016 and the first round of the main draw to Angelique Kerber last year.
ORDER OF PLAY
NATIONAL TENNIS STADIUM (starts 12.30pm)
Lucie HRADECKA (CZE) / Ekaterina MAKAROVA (RUS)  vs Gabriela DABROWSKI (CAN) / XU Yifan (CHN) 
Not before 2.30pm
Anastasija SEVASTOVA (LAT) vs Naomi OSAKA (JPN) 
After 1 ATP match, not before 7.30pm
[WC] WANG Qiang (CHN) vs Caroline WOZNIACKI (DEN) 
LOTUS COURT (starts 2pm)
Elise MERTENS (BEL) / Demi SCHUURS (NED)  vs Andrea SESTINI HLAVACKOVA (CZE) / Barbora STRYCOVA (CZE)