<p class="title">Five-time Grand Slam champion Maria Sharapova came back from a set down to defeat American Alison Riske at the Shenzhen Open today and book a spot in the quarterfinals.</p>.<p class="bodytext">Riske, who had been hoping for her first win against the former world number one, proved to be a tough opponent early in the match before the Russian finally overcame her 3-6, 6-4, 6-2 in just under two and a half hours.</p>.<p class="bodytext">"I'm glad I got this kind of match. Although I would've wanted a quick and easy victory, these are the kind of matches that you need, especially with such a short preparation going into the Australian Open in terms of matchplay," Sharapova said afterwards.</p>.<p class="bodytext">"I'm just glad that I came back. She played a really great match and as I said to her at the net, I thought it was a great quality match. In the end, I won it so I have another opportunity to keep going."</p>.<p class="bodytext">Despite Riske's early lead, Sharapova hit 34 winners, nearly three times Riske's total.</p>.<p class="bodytext">The world number 59 was helped by 11 aces, and managed to save seven out of 10 break points.</p>.<p class="bodytext">French Open champion Jelena Ostapenko meanwhile slumped to a shock defeat on Tuesday only days after beating Serena Williams in the American's comeback match.</p>.<p class="bodytext">Number two seed Ostapenko of Latvia lost to the big- serving Czech Krystina Pliskova 6-1, 6-4 in just an hour and 20 minutes.</p>.<p class="bodytext">Ostapenko had beaten Williams via a super tie-break 6-2, 3-6, 10-5 in Abu Dhabi on Saturday, but she had no answer to the power of Pliskova, identical twin sister of former world number one Karolina.</p>.<p class="bodytext">"I felt a bit nervous in the second set, but my serve was really working today, which was a big help," Pliskova said after the match.</p>.<p class="bodytext">Pliskova, third on the WTA Tour's ace charts last season, raced out to a 5-0 lead to start the match.</p>.<p class="bodytext">"My serve was great today, especially in the first set. I feel like it's really fast here, so that can be tricky for both of us, and the first of us playing fast won the point."</p>.<p class="bodytext">It was not the start to 2018 that Ostapenko wanted, with the first Grand Slam of the year -- the Australian Open -- starting in 13 days' time.</p>.<p class="bodytext">Earlier there was disappointment for the home crowd when Chinese number three seed Zhang Shuai was bundled out in three sets by Kazakhstan's Zarina Diyas.</p>
<p class="title">Five-time Grand Slam champion Maria Sharapova came back from a set down to defeat American Alison Riske at the Shenzhen Open today and book a spot in the quarterfinals.</p>.<p class="bodytext">Riske, who had been hoping for her first win against the former world number one, proved to be a tough opponent early in the match before the Russian finally overcame her 3-6, 6-4, 6-2 in just under two and a half hours.</p>.<p class="bodytext">"I'm glad I got this kind of match. Although I would've wanted a quick and easy victory, these are the kind of matches that you need, especially with such a short preparation going into the Australian Open in terms of matchplay," Sharapova said afterwards.</p>.<p class="bodytext">"I'm just glad that I came back. She played a really great match and as I said to her at the net, I thought it was a great quality match. In the end, I won it so I have another opportunity to keep going."</p>.<p class="bodytext">Despite Riske's early lead, Sharapova hit 34 winners, nearly three times Riske's total.</p>.<p class="bodytext">The world number 59 was helped by 11 aces, and managed to save seven out of 10 break points.</p>.<p class="bodytext">French Open champion Jelena Ostapenko meanwhile slumped to a shock defeat on Tuesday only days after beating Serena Williams in the American's comeback match.</p>.<p class="bodytext">Number two seed Ostapenko of Latvia lost to the big- serving Czech Krystina Pliskova 6-1, 6-4 in just an hour and 20 minutes.</p>.<p class="bodytext">Ostapenko had beaten Williams via a super tie-break 6-2, 3-6, 10-5 in Abu Dhabi on Saturday, but she had no answer to the power of Pliskova, identical twin sister of former world number one Karolina.</p>.<p class="bodytext">"I felt a bit nervous in the second set, but my serve was really working today, which was a big help," Pliskova said after the match.</p>.<p class="bodytext">Pliskova, third on the WTA Tour's ace charts last season, raced out to a 5-0 lead to start the match.</p>.<p class="bodytext">"My serve was great today, especially in the first set. I feel like it's really fast here, so that can be tricky for both of us, and the first of us playing fast won the point."</p>.<p class="bodytext">It was not the start to 2018 that Ostapenko wanted, with the first Grand Slam of the year -- the Australian Open -- starting in 13 days' time.</p>.<p class="bodytext">Earlier there was disappointment for the home crowd when Chinese number three seed Zhang Shuai was bundled out in three sets by Kazakhstan's Zarina Diyas.</p>