STUTTGART - Maria Sharapova claimed a hat-trick of Stuttgart titles on Sunday after coming from behind to win a three-set battle royal with Ana Ivanovic in Sunday's final. Having won the 2012 and 2013 titles here, the 27-year-old Sharapova was made to work hard for her 13th consecutive win on Stuttgart's clay-courts in the 51st final of her career before over-powering Ivanovic to claim a 3-6, 6-4, 6-1 victory in just over two hours.It is the Russian's first clay-court tournament in her build-up to the French Open, having lost to Serena Williams in last year's final. Having been taken to three sets by the Czech Republic's Lucie Safarova in her first-round match, Russia's Sharapova had swept into the final with straight set wins over compatriot Anastasia Pavlyuchenkova, top-seed Agnieszka Radwanska of Poland, then Italian clay-court specialist Sara Errani in the semi-finals.But Ivanovic, the ninth seed, made the statuesque Russian dig deep and the 26-year-old wasted no time asserting herself over Sharapova, racing into a a 4-0 lead in the first set before the defending champion responded, but the Serbian held her serve to take the first set. Having won her previous tournament in Monterrey, Mexico, last month, Ivanovic went 3-1 up in the second but the match's momentum turned against her when Sharapova broke her, then fought her way back to take the set.Ivanovic had been chasing her first win over the Russian since the 2007 French Open semi-final, when Ivanovic went onto lose to Justine Henin in the final, but the Serbian ran out of steam and sixth seed Sharapova dominated the third set.Dimitrov beats Rosol for Bucharest title: Bulgaria's Grigor Dimitrov won his second ATP title of the year on Sunday when he defeated Lukas Rosol of the Czech Republic 7-6 (7/5), 6-1 in the final of the Bucharest Open. Ranked 16th in the world going into this week, Dimitrov, who previously had won in Acapulco where he defeated Andy Murray in the semi-finals, struggled against the big-hitting Rosol in the first set.The Bulgarian took a 2-0 lead in what was the pair's first meeting, but defending champion Rosol bounced back immediately. Rosol saved four set points from 15/40 at 5-6, before Dimitrov dominated the tie-break to wrap up the first set in 58 minutes. He then maintained the momentum by taking a 2-0 lead in the second set and broke Rosol for a third time, to love at 1-3 as he moved on to his 20th match win of 2014. Dimitrov had reached the final on Saturday when his French opponent, Gael Monfils, retired after just 16 minutes of their semi-final.