On the other courts, 13th seed Andrey Rublev is currently down *5-4 to in-form Hungarian Marton Fucsovics on Lenglen.
On Simonne-Mathieu, 22 year-old Paula Badosa leads *5-3 on Laura Siegemund and she will serve for the set.
Zhang Shuai has now called the trainer for what appears to be an issue with her right thigh. She has gone off the court for a medical timeout.
Zhang Shuai saves double break point to hold serve, forcing Kvitova to serve it out at *5-2. On the first set point, Kvitova just narrowly failed to complete a nice move to the forecourt, dropping a backhand volley into the net.
On the second, Zhang swept forward to the net herself, perfectly timing a lovely backhand drive volley. After a wayward forehand return from Kvitova, she has now established some momentum even if the match moves into a third set. Kvitova leads *5-2.
This has not been a good start for Zhang Shuai, but she is a really talented player with a great story. Between 2008 and 2015, Zhang lost in her first fourteen slam first rounds despite numerous good results on the WTA tour. Her struggles eventually led to her considering retirement at the end of 2015.
Zhang’s family and close friend Sam Stosur convinced her to play on and she arrived at the 2016 Australian Open thinking she would give it one last try. Zhang drew world number two Simona Halep in the first round, and beat her in straight sets before reaching the quarters. After all those struggles at slams, she has now reached the second week of all but the US Open.
Great effort from Kvitova to save break point with a big serve down the T before holding firm through a long deuce game to reach 5-1*. She served very well when needed.
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The conditions have forced Kvitova to be really disciplined and creative with her shot selection. She still has the power to hit through the courts, but she has stepped onto the court knowing that points simply will not come as easily for her as usual. If she tries to blast through opponents, she will lose. That is a completely different mentality than on faster courts when she can just spend the whole time on the front foot.
We’re already seeing her playing the margins more by opening up the court with cross-court angles and choosing her moments to change directions very carefully. That was exemplified by her game point for 4-0, in which she was pushed back behind the baseline by a Zhang. Instead of crushing her backhand down-the-line, she slotted an angled backhand behind Zhang. Still, a good hold from Zhang to get on the board. Kvitova leads 4-1.
Petra Kvitova did not have a similar quality start in Saturday’s match against 18 year old Leylah Fernandez, where she quickly found herself down 1-5 in the first set before facing two set points. However, it was really impressive how she dug herself out of that hole.
Kvitova’s peerless ballstriking talent is well known to most but as she has grown up, she has learnt how to harness her weapons more consistently, to think more on-court and to problem solve in matches. Not many players have as many shots in their arsenal as Kvitova, who is very comfortable throwing in drop shots, slices, angles and moving into the net. That variety of shot helped her win 9 games in a row from 1-5 down on in her third round.
Not many people fancied Kvitova this week in slow, wet conditions on a clay court at the start of last week, but she is still here and she looks good. After a couple of double faults from Zhang, Kvitova now leads *3-0 with a double break.
This has been a quality start from Petra Kvitova on Chatrier, who broke in the opening game and then quickly held to consolidate for a 2-0 first set lead against Zhang Shuai, sealed with a beautiful running forehand cross-court winner.
Hello! Welcome to day nine of our Roland Garros coverage as fourth round action comes to a conclusion. After a series of shock results in the women’s draw over the past couple of days, with 2018 champion Simona Halep, 2016 champion Garbine Muguruza and 5th seed Kiki Bertens being knocked out, we begin on Chatrier with one of the two remaining slam champions in the draw as Petra Kvitova takes on Zhang Shuai of China. Stefanos Tsitsipas will follow in a single-handed backhand duel against Grigor Dimitrov before Australian Open champions Novak Djokovic and Sofia Kenin finsh off play on Chatrier.
While the women’s draw has quickly descended into chaos, with a new Roland Garros champion certain to be crowned, this week so far has been a stroll for Djokovic and Rafael Nadal. The question is who will first be able simply put them under any pressure at all. 15th seed Karen Khachanov of Russia will have his chance today.
Today’s order of play:
Court Philippe Chatrier Petra Kvitova vs Shuai Zhang  Grigor Dimitrov vs  Stefanos Tsitsipas  Novak Djokovic vs  Karen Khachanov
Fiona Ferro vs  Sofia Kenin
Court Suzanne Lenglen
Marton Fucsovics vs  Andrey Rublev Ons Jabeur vs Danielle Collins  Pablo Carreno Busta vs Daniel Altmaier
Laura Siegemund vs Paula Badosa Kuzmova/Kr.Pliskova vs  Krejcikova/Siniakova Cabal/Farah vs Nielsen/Puetz
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