Serena Williams vs. Agnieszka Radwanska takes place tonight at the TEB BNP PARIBAS WTA Championships.
The WTA Championships match takes place on Centre Court and is scheduled to start at 19:00 BST.
In the UK, the game airs live on Eurosport 2/Eurosport 2 HD, while it is also streaming live online with bet365.
Watch Azarenka vs. Radwanska live here:
Radwanska will have to muster all her determination to try and overturn a 0-7 head-to-head deficit against the World No. 1 this evening.
Radwanska found herself down early breaks in both sets on Monday as Petra Kvitova simply over-powered her, as the Czech closed out a straight sets victory 6-4 6-4 - something she could joke about afterwards, given her knack of gritting out three-setters.
It was no joking matter for the Pole though, who has to come back today to face the defending champion who looked sharp as she breezed past Angelique Kerber 6-3 6-1. It must be daunting to know that Williams' serving is spot on.
"But I feel really good actually. I think I served really well," Serena said after her first match of the week.
"She's beaten me before so I was really a little nervous and so focused going into this match. I really felt like I had to play well to win today."
Radwanska has a good all-court game and will need to pull out every trick in the book to try and catch a dialled-in Williams off balance. Her serve is what will let her down, especially when coupled with Williams’ lightning quick reflexes on return, and if she surrenders an early break, it is hard to see Williams not capitalising on another chance to rout the opposition.
Radwanska has pushed her close this year, with probably her best performance against the World No. 1 in Toronto this year and she will need to play with all that fortitude to keep pace.