Nadal, Federer set up semi-final clash

World No 2 Rafael Nadal and world No 3 Roger Federer set up their first semi-final clash at the Indian Wells ATP Masters with contrasting victories over Argentinian opponents on Friday. Nadal, who is chasing his first title of 2012, survived an opening set scare en route to a 4-6, 7-5, 6-4 win over David Nalbandian in their quarter-final match. Swiss star Federer had a much easier time, rolling to a 6-3, 6-2 win over a frustrated Juan Martin del Potro in the joint WTA/ATP tournament in the California desert. Federer and Nadal have met 27 times previously, with Nadal having won 18, including four of the last five. \"We played 27 times. It will be the first time here at Indian Wells,\" Nadal said. \"Tomorrow, I have a fantastic match to enjoy and to try to play aggressive.\" Federer added, \"I have had some great matches with him all around the world by now.\" But, this will be the first time 16-time Grand Slam winner Federer and reigning French Open champ Nadal will meet on the hardcourts of Indian Wells. World number one Novak Djokovic faced American John Isner in the other semi-final on Friday. Nadal, who hit three aces, clinched the victory in the 10th game of the final set on Friday when Nalbandian\'s running backhand went wide. Nalbandian\'s momentum carried him forward and he almost crashed into his chair but managed to kick it over instead. He then congratulated Nadal on the win. \"It was very difficult,\" Nadal said. \"I was a little bit more nervous than usual. It is a very important victory because I will now be in the semi-finals here. I am excited and happy. The Nalbandian threat \"Nalbandian always gives me problems on my game, and that probably makes me feel a little bit not safe before the match. That\'s why probably I had more mistakes than usual.\" World number one Victoria Azarenka of Belarus, meanwhile, charged into the final 6-4 6-3 victory over Germany\'s Angelique Kerber on Friday. Both players struggled to hold serve in breezy conditions on the showpiece stadium court but Azarenka sealed the win by breaking her 18th-seeded opponent in the ninth game of the second set when the German hit a forehand long. Australian Open champion Azarenka will face second-seeded Maria Sharapova in today\'s final after 2008 winner Ana Ivanovic of Serbia retired hurt from the second semi-final because of an injured left hip while trailing the Russian 6-4, 0-1. The title showdown at the Indian Wells Tennis Garden will be a repeat of the Australian Open final in January when Azarenka won her first Grand Slam title with a crushing 6-3 6-0 victory over Sharapova. Emotional Ivanovic \"I can\'t play, I can\'t push,\" a tearful Ivanovic told the chair umpire before withdrawing from her match in the last four. Ivanovic had taken a medical time-out after the ninth game of the first set before returning to the court for two more games, and exiting with Sharapova 30-0 up on her serve. \"After the treatment, it was just getting worse and worse rapidly,\" the 24-year-old Serb later told reporters. \"We taped it and then I tried to continue, but at the end, I couldn\'t even return. \"I\'m very disappointed ... I really felt like I have been playing the best tennis probably played in a very, very long time\".