ANN JONES CENTRE COURT
Starts at 11.30am BST
Lucie SAFAROVA (CZE) vs Daria GAVRILOVA (AUS) 
Kristina MLADENOVIC (FRA)  vs Petra KVITOVA (CZE) 
Garbiñe MUGURUZA (ESP)  vs CoCo VANDEWEGHE (USA)
Ashleigh BARTY (AUS) vs [Q] Camila GIORGI (ITA)
Starts at 12 noon BST
CHAN Hao-Ching (TPE) / ZHANG Shuai (CHN) vs Shuko AOYAMA (JPN) / YANG Zhaoxuan (CHN)
Lucie SAFAROVA (CZE) / Barbora STRYCOVA (CZE)  vs Sania MIRZA (IND) / Coco VANDEWEGHE (USA)
CoCo Vandeweghe owns a 3-1 head-to-head lead over Garbiñe Muguruza - and those three wins have all helped the American meet significant milestones. In 2014, Muguruza was Vandeweghe's quarterfinal conquest en route to her first title in 's-Hertogenbosch; a week later, another victory over the Spaniard in the first round of Wimbledon propelled the American into the Top 50 for the first time. And this year, a 6-4, 6-0 thumping in the Australian Open quarterfinals enabled Vandeweghe to make her Slam semifinal debut.
Lucie Safarova leads the head-to-head against Daria Gavrilova 3-2, including a 6-2, 6-2 win this year in the second round of Miami - but today's quarterfinal will be the first time they have played on grass.
Grass has historically been a surface of career milestones for Ashleigh Barty. The Australian was the Wimbledon girls' champion in 2011 (beating Madison Keys en route), and a year later took her first ITF $50,000 event in Nottingham (scoring a win over Karolina Pliskova). In 2016, she made her comeback from a two-year hiatus in the grass swing and immediately compiled a 12-3 record on it. Today, she plays her first career Premier-level quarterfinal against Camila Giorgi, whom she beat 6-3, 6-0 in their only meeting, in Strasbourg last month.
Petra Kvitova leads the head-to-head 3-1 against Kristina Mladenovic, but they have not played since the 2015 Fed Cup semifinals. Mladenovic's sole win came indoors in Paris in 2013.
This week marks just the second time CoCo Vandeweghe has won consecutive WTA Tour matches since her Australian Open semifinal run in January.