Former champion Maria Sharapova bowed out of the Australian Open at the first hurdle on Tuesday following a 6-3, 6-4 to Donna Vekic on Rod Laver Arena. The Russian, 32, champion at Melbourne Park in 2008, was clearly still hampered by the shoulder injury that had restricted her to one previous competitive outing since her opening-round exit at last year's US Open. Croatian Vekic proved a formidable and the 19th seed raced to a 5-1 lead in the opening set before the former world No 1 found a way to get back into the contest. Sharapova made Vekic work hard to close out the set and took a 4-1 lead in the second but was unable to maintain her momentum, losing the last five games to make her earliest exit from Melbourne Park since 2010. Five-time Grand Slam champion Sharapova cut a forlorn figure in the post-match press conference as she was questioned about her injury problems. "I'm not the only one," she said. "You know, I can speak about my struggles and the things that I've gone through with my shoulder, but it's not really in my character to. "So, I was there. I put myself out there. As tough as it was, I finished the match and, yeah, it wasn't the way that I wanted." Asked directly whether her 15th visit to Melbourne Park might be her last, Sharapova said there were no guarantees. "I don't know. I don't know," she said. "I was fortunate to get myself to be here and thanks to [the organisers for] allowing me to be part of this event. "It's tough for me to tell what's going to happen in 12 months' time." Second seed Karolina Pliskova got exactly what she needed in her 6-1, 7-5 victory over a determined Kristina Mladenovic on Rod Laver Arena to advance to the second round. Czech Pliskova will next play either Germany's Laura Siegemund or American wildcard CoCo Vandeweghe. Pliskova, a semi-finalist at Melbourne Park last year, was at her imperious best with her groundstrokes in a 25-minute first set she totally dominated despite a wayward serve. Mladenovic, however, stepped up her game in the second, the 26-year-old Frenchwoman moving Pliskova around the court more and the Czech was forced to work harder for her points and improve a first serve that landed just 50 per cent in the first set. She upped that to 78 per cent in the second and won the points that mattered to continue a perfect start to 2020 <a href="https://www.thenational.ae/sport/tennis/karolina-pliskova-wins-in-brisbane-but-starts-from-zero-heading-into-australian-open-1.963160">after she won the Brisbane International title last week</a>. "I think it was quite good for first match," Pliskova told reporters. "Of course the match was not easy. So I think, yeah, it was a good test for a first round." The only resistance Mladenovic put up early on was in the nine-minute third game when she held two break points, but world number two Pliskova was able to fight them off. Mladenovic managed to get on the board when she finally held in the sixth game, but Pliskova served out in the next game, wrapping up the first set with her second ace in 36 minutes. Such was Pliskova's dominance in the first set Mladenovic failed to win a point in four of the seven games. Mladenovic was far better in the second set and while she was broken for the third time in the match to give Pliskova a 4-3 advantage, she converted the first of her seven break opportunities in the next game. She then held to take a 5-4 lead but any hope of extending the match to a decider fizzled as Pliskova won the next three games to seal her spot in the second round. "I think it starts always with me," said the Czech. "If I play good and fast enough, deep enough, then there is not much she can do. "So it was ... mainly about me, because I thought if I can just play good tennis, I think I'm going to be fine, which I kind of was."