Serena Williams is through to the semifinals, but five players are battling it out for the other three spots in the final four - what do they need to do to qualify? That and more, right here - read on!
WTA Staff

ISTANBUL, Turkey - Every day we will bring you 10 things to look for on the court in Istanbul - stats, nuggets, upcoming milestones, head-to-heads. Get your fix on all of that for Day 4, right here.


First Place: Serena
Second Place: Winner of Kvitova Vs Kerber

Two of Azarenka, Li and Jankovic will qualify - see the below chart for scenarios, with the possible match results along the top and side and the resulting top two finishers for the group in the cells...

White Group

(play begins at 5pm Istanbul time - watch live here)

(2) Victoria Azarenka (BLR #2) vs (4) Li Na (CHN #5)
Head-To-Head: Azarenka leads Li, 6-4.

Azarenka has beaten Li five times in a row.
Azarenka has turned a 1-4 head-to-head record against Li into 6-4 with five wins in a row, which includes two wins in the round robin stage here the last two years - 62 62 in 2011, 76(4) 63 in 2012.

Azarenka will be the year-end World No.2.
Serena and Azarenka have secured the year-end No.1 and No.2 rankings, respectively.

Li could be the year-end World No.3.
If Li loses today, she would still rise to No.3 if she goes on to win the title. If she wins today, she would rise to No.3 just by getting to the final (she wouldn't even need to win the title). If she gets to No.3, it would not only be her new career-high, she would be the highest-ranked Asian player ever.

Li has five career wins over Top 2 players.
Two over No.1s (Serena at 2008 Stuttgart, Wozniacki at 2011 Aussie Open) and three over No.2s (Sharapova at 2011 WTA Championships, Kvitova at 2012 Sydney, Sharapova at 2013 Aussie Open).

(5) Petra Kvitova (CZE #6) vs (8) Angelique Kerber (GER #9)
Head-To-Head: Kvitova is tied with Kerber, 2-2.

These are by far the Top 2 left-handers in the world.
At No.6 and No.9, Kvitova and Kerber are the two highest-ranked lefties. Next is No.24 Makarova.

Kvitova has done much better than Kerber against fellow lefties this year.
Kvitova is 7-1 against lefties this year; Kerber is 2-3 against lefties this year.

This will be just the third time since 1992 that a lefty will be in the semifinals at this event.
Since Navratilova was runner-up at this event in 1992, this will only be the third time a lefty is in the semifinals: 2000 (Seles - runner-up), 2011 (Kvitova - champion) and 2013 (one of these two).

Both Kvitova and Kerber love playing on indoor hardcourts.
Kvitova is 30-4 on indoor hardcourts since the start of 2011, while all three of Kerber's WTA titles have come on indoor hardcourts (Paris [Indoors] and Copenhagen in 2012, Linz just a few weeks ago).

(6) Sara Errani (ITA #7) vs (7) Jelena Jankovic (SRB #8)
Head-To-Head: Jankovic leads Errani, 1-0.

The only time these two met, it was about as close as you can get.
A No.9-ranked Jankovic beat a No.49-ranked Errani in the third round of Indian Wells in 2010, 26 76(6) 64. Jankovic was two points from losing at 6-all in the second set tie-break, and she was also in deep trouble in the third set - she was on the verge of going down a double break, serving at 2-4, 0-40.

Errani has done much better against Top 10 players in the last 17 months than before.
Errani went into the 2012 French Open with an 0-28 record against Top 10 players, and while she doesn't have a winning record against Top 10 players since then, it's still a much better 6-17 (26.1%).