EASTBOURNE: Samantha Stosur has delivered a serving masterclass to scorch into the semi-finals of the pre-Wimbledon event at Eastbourne.Contesting her seventh consecutive WTA quarter-final, Stosur thundered down 15 aces in an impressive 6-7 (5-7), 6-1, 6-0 win over high-flying Scot Elena Baltacha.Victory set up a showdown on Friday with either 2009 French Open champion Svetlana Kuznetsova or fellow Russian Ekaterina Makarova.With Wimbledon just around the corner, Stosur said she’d been practising her serve ”over and over” to ensure she gets full value from her big kicker on the London lawns when the season’s third grand slam gets underway on Monday.”On the grass, it’s even more important,” Stosur said after highlighting her point in emphatic fashion yesterday.Living dangerously, Stosur probably didn’t need to fuel Baltacha’s confidence by handing her the opening set with a meek netted backhand in the tiebreaker.But the French Open runner-up was a completely different player from then on, banging winners from all parts of the court to blow Baltacha away.After breaking the Brit’s serve twice, Stosur unleashed a hat-trick of aces to grab a 4-0 lead before quickly going on to draw level at a set apiece.It was one-way traffic in the deciding set, the third-seeded Stosur refusing to drop a single game.Belgian Kim Clijsters, meantime, reached the quarter-finals, needing only 38 minutes to sweep aside Czech left-hander Lucie Safarova 6-1, 6-0 and continue her good form in the Wimbledon warm-up tournament.Clijsters, playing her first tournament since injuring her foot in a Fed Cup tie in April, has dropped only three games in her first two matches. She allowed Safarova only seven points in the second set.”It was a good one, quick and perfect,” Clijsters said.”I feel that I’m moving well. I feel that my foot is holding up good and obviously those were my main concerns, especially the foot, when I first got here.”? Meanwhile, Bernard Tomic has reached the Wimbledon men’s main draw with a final-round qualifying victory over talented Indian Prakash Amritraj.Tomic, a two-times grand slam junior champion, outclassed the Indian 7-6 (7-3) 6-3 6-4 yesterday.The 17-year-old prodigy joins 2002 champion Lleyton Hewitt and fellow Australian Peter Luczak in the 128-man draw for the grasscourt grand slam starting on Monday.Carsten Ball and Matthew Ebden were hoping to further swell the Australian contingent when they contest their final-round qualifying matches later in the day.AP