Has Jelena Jankovic beaten Serena Williams when she was No.1? Is Li Na really better against lefties? Have two 30-somethings ever made the final four here? Want doubles nuggets? Read on...
WTA Staff

ISTANBUL, Turkey - Every day we've been bringing you stats, nuggets, milestones, head-to-heads and more on all the matches at the TEB BNP Paribas WTA Championships - Istanbul. Now it's down to the business end of the tournament and we're not stopping - read up on Saturday's matches here...

(watch Saturday's coverage live on WTA Live powered by TennisTV)


(4) Li Na (CHN #5) vs (5) Petra Kvitova (CZE #6)
Head-To-Head: Li and Kvitova are tied, 3-3.

Li will be World No.3, and the highest-ranked Asian player ever, if she wins today.
~ Li will go from No.5 to No.3 if she wins today, surpassing her previous career-high of No.4, where she is tied with Kimiko Date-Krumm for the highest ranking ever for an Asian player, male or female.

Li is better against lefties than righties.
~ This year, Li is 5-1 against lefties (5:1) and 38-12 against righties (about 3:1). Since coming back from a six-month rib injury lay-off at the start of 2008, so over the last six years, this trend is even stronger, with Li going 39-6 against lefties (6.5:1) and 178-92 against righties (about 2:1).

This is 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 is only the third time a lefty is in the semifinals: 2000 (Seles - runner-up), 2011 (Kvitova - champion) and 2013 (Kvitova again).

Kvitova loves playing on indoor hardcourts.
~ Kvitova is 31-4 on indoor hardcourts since the start of 2011. Two of those four losses came in 2012 (to Radwanska and Ivanovic) and two have come this year (to Mladenovic and Serena - this week).

(1) Serena Williams (USA #1) vs (7) Jelena Jankovic (SRB #8)
Head-To-Head: Serena leads Jankovic, 7-4.

Jankovic is one of only two active players with four or more wins over Serena.
~ Serena has lost four times to Jankovic (7-4 overall) and 10 times to Venus (14-10 overall).

Jankovic has beaten Serena when she was No.1.
~ Jankovic is 3-14 against World No.1s - broken down that's 0-1 against Davenport, 0-2 against Mauresmo, 0-6 against Henin, 2-0 against Safina, 1-2 against Serena and 0-3 against Wozniacki.

Jankovic's win over a No.1-ranked Serena was pretty historic (read more about that victory here).

Jankovic is trying to beat the Top 2 at the same event for the first time in her career.
~ Jankovic beat No.2 Azarenka in the round robin and now faces No.1 Serena. She has never done it before, and no one has done it this year (the last player to do it was Serena at this event last year).

Serena hasn't lost a set to anyone other than Venus at the WTA Championships since 2007.
~ In her first round robin match in 2007, Serena dropped the first set to Chakvetadze then retired with a knee injury - that was the last set she has lost to anyone at this event other than Venus (since then at this event, she is 5-3 in sets against Venus and 24-0 in sets against everyone other than Venus).


This is second time in WTA Championships history that two 30-somethings are in the final four.
~ With Serena and Li in the semifinals, it's just the second time it has happened since this tournament began in 1972 (in 1973, 30-year-old Durr was a semifinalist and 31-year-old Richey was runner-up).


(1) Errani/Vinci (ITA/ITA) vs Makarova/Vesnina (RUS/RUS)
Head-To-Head: Errani/Vinci lead Makarova/Vesnina, 4-1.

(2) Hsieh/Peng (TPE/CHN) vs Petrova/Srebotnik (RUS/SLO)
Head-To-Head: Hsieh/Peng and Petrova/Srebotnik are tied, 1-1.

These teams represent three of this year's four Grand Slam doubles champions.
~ Errani and Vinci won the Australian Open, Makarova and Vesnina won the French Open and Hsieh and Peng won Wimbledon. The only Grand Slam doubles champions missing are Hlavackova and Hradecka, who won the US Open (they finished No.6 in the race - Barty/Dellacqua finished No.5).

Hsieh and Peng have won the most WTA doubles titles together this year of the four teams.
~ Hsieh and Peng four, Errani and Vinci and Petrova and Srebotnik three, Makarova and Vesnina two.

None of these eight players have the most individual WTA doubles titles this year.
~ The most individual WTA doubles titles any of these players has is four. There are two players who have five WTA doubles titles this year - Mirza (with three partners) and Mladenovic (with five partners).

One of them does have the most individual WTA doubles match wins this year, though.
~ Srebotnik has the most WTA doubles match wins this year with 54 (Mirza is next with 43).