There's a reason she's No.1 and the first $7 million woman - she never gives up. Like, ever.
WTA Staff

ISTANBUL, Turkey - When the Top 8 players assemble in one city, not only are there going to be thrills on the court, but some great nuggets for all of the stats fans out there. This week will bring you stats to chew on, from that day's matches to scenarios to some other Turkish delights...

Thursday: Round Robin, Day 3.

(5) Angelique Kerber (GER #5) vs. (8) Li Na (CHN #8)
~ Head-To-Head: Li leads Kerber, 5-1
~ Li has dominated the series, but Kerber does have one win (and a recent one too, at Indian Wells this year) and came close in two of Li's wins (falling 7-5 in the third set at Birmingham in 2010 and leading 61 31 at Cincinnati this year before falling, 16 63 61); Kerber wrote in her blog from Cincinnati, "Li Na was playing so well, especially the last set. My goal was to give everything I had and I think I did that - she just got better and better during the match."

Kerber Notes
~ So far this week the highest-ranked player has won every match (6-0); but with Li's 5-1 head-to-head lead over Kerber and Williams' 10-1 head-to-head lead over Azarenka, this stat could be under significant threat today
~ Kerber's two career WTA titles have both come on indoor hardcourts (both earlier this year, at Paris [Indoors] and Copenhagen)
~ Kerber is the only player in the Top 12 not to have reached a Grand Slam final (she is a two-time semifinalist); the next-highest-ranked player never to have reached a Grand Slam final is No.13 Petrova (also a two-time semifinalist)

Li Notes
~ In the last five years Li has been way better against lefties than righties: 33-5 against lefties (6.6 to 1) and 140-79 against righties (1.8 to 1)
~ Li is the only member of the elite eight not to reach a Grand Slam quarterfinal this year (fourth round at Australian Open, fourth round at French Open, second round at Wimbledon, third round at US Open); the other seven players here reached at least two Grand Slam quarterfinals each this year
~ With Li and Williams in the field, this is the first time two 30-somethings have played the WTA Championships since 2001 (Tauziat and Coetzer)

(1) Victoria Azarenka (BLR #1) vs. (3) Serena Williams (USA #3)
~ Head-To-Head: Williams leads Azarenka, 10-1
~ Azarenka snuck out one win over Williams, in the final of Miami in 2009 - though Williams came out with her thigh heavily taped in that match; Williams has won all 10 of their other meetings, although a few of them have been very, very close (Azarenka led 64 40 in the 2010 Australian Open quarterfinals and, more recently, led 5-3 in the third set of the 2012 US Open final)

Azarenka Notes
~ Azarenka can secure the year-end No.1 ranking by winning this match
~ By taking the court for her first round robin match (win or lose), Azarenka passed $7 million for the season, the first WTA player ever to pass that mark (the previous single season record was $6,545,586 - Williams in 2009)
~ Azarenka is 14-0 since the US Open, though while her other 13 matches came in straight sets, she was pushed to the limit in the 14th - her first round robin match here (saving two match points to beat Kerber, 67(11) 76(2) 64)

Williams Notes
~ Williams certainly lifts her game against top players: she has won 15 matches in a row against Top 5 players (last loss: No.3 Zvonareva at 2011 Eastbourne), 10 in a row against Top 2 players (last loss: No.2 Kuznetsova at 2007 Moscow) and five in a row against No.1s (last loss: No.1 Henin at 2007 US Open)
~ Williams has the equal-second-most wins over World No.1s in WTA history with 15 (Davenport also had 15 - Navratilova has the most all-time with 18)
~ Williams has won 45 of her last 47 matches (the two losses came to Razzano in the first round of Roland Garros and to Kerber in the quarters of Cincinnati)

(7) Sara Errani (ITA #7) vs. (Alt) Samantha Stosur (AUS #9)
~ Head-To-Head: Stosur leads Errani, 5-1
~ Stosur won their first five meetings, four in straight sets and a 61 36 76(4) thriller at New Haven in 2010 (Errani held four match points at 5-4 third set); Errani won their last meeting in the French Open semifinals this year

Errani Notes
~ Errani was 0-28 against Top 10 players going into the French Open this year and is 4-4 since then (the wins came against Kerber and Stosur at the French Open, Kerber again at the US Open and Bartoli at Tokyo [Pan Pacific])
~ Errani is one of three Italians ever to reach the Top 10, peaking at No.7 (Pennetta went as high as No.10 and Schiavone went as high as No.4)

Stosur Notes
~ Has been called on as an alternate after Kvitova withdrew due to illness; since the WTA Championships switched to the current round robin format an alternate has been called on seven times now (and they have a 4-3 record)
~ Stosur has been a direct entrant twice here, reaching the semifinals in both 2010 (lost to Clijsters) and 2011 (lost to Kvitova)
~ Stosur can reach the semifinals this year too, but only if she wins both of her round robin matches AND have Errani beat Radwanska on Friday

BONUS STAT: Comeback Queen Azarenka
Azarenka's 61-0 record this year after winning the first set is just one of the reasons she's firmly the No.1 player in the world right now - she is also quite a threat when she's behind, as evidenced by her win over Kerber on Wednesday. Here's a look at some of her comebacks from her career year this year:

~ Indian Wells, Second Round - d. Barthel, 64 67(4) 76(6)... down 4-1 third set
~ Miami, Fourth Round - d. Cibulkova, 16 76(7) 75... down 61 52
~ Stuttgart, Quarterfinals - d. Barthel, 64 67(3) 75... down a break third set
~ French Open, First Round - d. Brianti, 67(6) 64 62... down a set and 4-0
~ WTA Championships, Round Robin - d. Kerber, 67(11) 76(2) 64... saved two match points down 5-4 second set

No matter how far behind she is, Azarenka should never be counted out...

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