Serena Williams on Thursday served a perfect first set on her way to setting up a blockbuster semi-final against Maria Sharapova at the Brisbane International. The top-seeded Williams didn't lose a point on serve in the opening set during her 6-3, 6-3 win over Slovakia's Dominika Cibulkova. In stark contrast to Williams, Sharapova was forced to recover from an error-strewn start before eventually downing 2012 champion Kaia Kanepi in three sets, 4-6, 6-3, 6-2. Today's semi-final will be the 17th meeting between the two superstars of the women's game, who make no secret of their frosty personal relationship. Williams holds a clear advantage over the Russian, winning 14 times against Sharapova, including the last 13 in a row. Their most recent clash was in the final of last year's French Open, where Williams won a tight battle 6-4, 6-4. "Some of the matches were a bit closer than others," Sharapova said of her run of 13 losses. "I know I've tried and I didn't succeed in the last many times that I've played her, but I'm setting up an opportunity to go out there and try to change that, and I'm going to try to do that." Williams, who lost only four times in 2013, was in irresistible form against Cibulkova. The world number one said she had been working on her serve in the off-season, but was still surprised at not losing a point in the first set for the first time since juniors. "She was returning really well, she stays so low to the ground and does so many good things, especially off the ground. She's just so powerful," Williams said. "So of all the opponents, I definitely wouldn't expect it against her. But I was able to serve really well today." The defending champion was so focused beforehand she almost went on court without her racquets, with WTA supervisor Donna Kelso having to remind her to take them with her. "I was just ready to get on this court, ready to play," a laughing Williams said. "I was just ready to get it started. I don't know - I just forgot 'em." Earlier, Sharapova and Kanepi appeared overcome by nerves at the beginning of their match. Both players hit 23 unforced errors in the first set but Sharapova began to reduce her error rate in the second and found the length with her groundstrokes, breaking Kanepi twice to level the match. She then raced away with the third in 33 minutes as her first service percentage lifted from 40 to 84. The second semi-final will be between second seed Victoria Azarenka, who survived a second-set meltdown when she blew eight match points to beat Swiss Stefanie Voegele 6-4, 6-7 (7-9), 6-1, and fourth seed Jelena Jankovic. Jankovic was a 6-7 (8-10), 6-3, 6-1 winner over Germany's Angelique Kerber.