<p>Li Na rolled past a visibly struggling Victoria Azarenka at the WTA Championships to advance to the semifinals from the White Group here on Friday.<br /><br /></p>.<p>The Chinese’s crushing 6-2, 6-1 victory over the second-seeded out-of-sorts Belarussian also enabled Jelena Jankovic make the cut for the last-four stage in the year-end bash.<br /><br />Li looked very sharp from the outset, her serve, groundstrokes and volleys hitting their mark time and time again as she stormed out to a 3-0 lead. Azarenka temporarily stopped her momentum, squeaking out two games in a row to close the gap to 3-2, but from there she was visibly struggling with an injury, and the fourth-seeded Li pounced with eight games in a row for a 6-2, 5-0 lead.<br /><br /> Azarenka scrounged up a hold of serve, but Li quietly served it out at love in the next game for a smooth win.<br /><br />“I know this is not the best way to win the match,” Li said in her on-court interview afterwards. <br /><br />“I saw her a little bit bothered with her back but she kept playing, so it was very tough for me mentally.<br /><br />“"If she were healthy she would have been a very tough opponent today. Unfortunately she wasn't healthy. I have to enjoy this moment, but I hope the injury isn't too bad and she can come back soon.”<br /><br />Serena Williams outslugged Petra Kvitova to become the first player to enter the semifinals on Thursday evening after the American crushed Petra Kvitova 6-2, 6-3 to complete her stroll through the Red Group.<br /><br />World No 1 Williams, looking to retain her title, has won all three matches at the Sinan Erdem Dome without a dropped set, leaving her rivals to scrap over the runners-up spot in the section.<br /><br />Kvitova, however, didn’t allow the pummelling to get the better of her, the Czech exhibiting good tenaciousness on Friday to beat Angelique Kerber 6-7, 6-2, 6-3 to seal the fourth and final semifinal spot.<br /><br />Del Potro shines<br /><br />Defending champion Juan Martin del Potro claimed his 300th match win as he cruised into the Swiss Indoors semifinals with a 6-4, 6-4 win over qualifier Paul-Henri Mathieu at Basel on Friday. <br /><br />The Argentine dominated on serve, hitting 11 aces and only surrendering six points overall to claim victory in 79 minutes.<br /><br />Del Potro has already secured his place at the season-ending ATP World Tour Finals and is bidding to win his fourth title of the season and reach his third final in a row. The Tandil native is coming off a strong Asian swing, which saw him win the Japan Open in Tokyo and defeat World No 1 Rafael Nadal to reach the Shanghai Masters final.<br /><br />Del Potro next will face World No 65 Edouard Roger-Vasselin, who reached his third ATP semifinal of the season as he as he battled past Daniel Brands 6-3, 4-6, 6-3. The Frenchman withstood 14 aces and saved four of the five break points he faced to prevail in just under two hours.<br /><br />Rising Canadian star Vasek Pospisil took another step forward on Friday as he defeated Ivan Dodig 7-6 (13-11), 6-4 to reach his third ATP semifinal of the season. <br /><br />The 23-year-old relinquished a break advantage in the second set, but broke decisively in the ninth game before serving out victory in one hour and 45 minutes.<br /></p>
<p>Li Na rolled past a visibly struggling Victoria Azarenka at the WTA Championships to advance to the semifinals from the White Group here on Friday.<br /><br /></p>.<p>The Chinese’s crushing 6-2, 6-1 victory over the second-seeded out-of-sorts Belarussian also enabled Jelena Jankovic make the cut for the last-four stage in the year-end bash.<br /><br />Li looked very sharp from the outset, her serve, groundstrokes and volleys hitting their mark time and time again as she stormed out to a 3-0 lead. Azarenka temporarily stopped her momentum, squeaking out two games in a row to close the gap to 3-2, but from there she was visibly struggling with an injury, and the fourth-seeded Li pounced with eight games in a row for a 6-2, 5-0 lead.<br /><br /> Azarenka scrounged up a hold of serve, but Li quietly served it out at love in the next game for a smooth win.<br /><br />“I know this is not the best way to win the match,” Li said in her on-court interview afterwards. <br /><br />“I saw her a little bit bothered with her back but she kept playing, so it was very tough for me mentally.<br /><br />“"If she were healthy she would have been a very tough opponent today. Unfortunately she wasn't healthy. I have to enjoy this moment, but I hope the injury isn't too bad and she can come back soon.”<br /><br />Serena Williams outslugged Petra Kvitova to become the first player to enter the semifinals on Thursday evening after the American crushed Petra Kvitova 6-2, 6-3 to complete her stroll through the Red Group.<br /><br />World No 1 Williams, looking to retain her title, has won all three matches at the Sinan Erdem Dome without a dropped set, leaving her rivals to scrap over the runners-up spot in the section.<br /><br />Kvitova, however, didn’t allow the pummelling to get the better of her, the Czech exhibiting good tenaciousness on Friday to beat Angelique Kerber 6-7, 6-2, 6-3 to seal the fourth and final semifinal spot.<br /><br />Del Potro shines<br /><br />Defending champion Juan Martin del Potro claimed his 300th match win as he cruised into the Swiss Indoors semifinals with a 6-4, 6-4 win over qualifier Paul-Henri Mathieu at Basel on Friday. <br /><br />The Argentine dominated on serve, hitting 11 aces and only surrendering six points overall to claim victory in 79 minutes.<br /><br />Del Potro has already secured his place at the season-ending ATP World Tour Finals and is bidding to win his fourth title of the season and reach his third final in a row. The Tandil native is coming off a strong Asian swing, which saw him win the Japan Open in Tokyo and defeat World No 1 Rafael Nadal to reach the Shanghai Masters final.<br /><br />Del Potro next will face World No 65 Edouard Roger-Vasselin, who reached his third ATP semifinal of the season as he as he battled past Daniel Brands 6-3, 4-6, 6-3. The Frenchman withstood 14 aces and saved four of the five break points he faced to prevail in just under two hours.<br /><br />Rising Canadian star Vasek Pospisil took another step forward on Friday as he defeated Ivan Dodig 7-6 (13-11), 6-4 to reach his third ATP semifinal of the season. <br /><br />The 23-year-old relinquished a break advantage in the second set, but broke decisively in the ninth game before serving out victory in one hour and 45 minutes.<br /></p>