Federer reaches Indian Wells semi-finals

World No. 3 Roger Federer rolled to an easy 6-3, 6-2 win over Juan Martin del Potro to reach the semi-finals of the Indian Wells WTA/ATP tennis tournament on Friday. The 30-year-old Swiss continued his dominance of Argentina\'s del Potro, beating him for the fifth consecutive time -- all in straight sets. \"It is a great win against an Argentine,\" Federer said. \"It is the fourth time I have played him this year. I thought I played really well. This is great.\" In the semi-finals, Federer will play either Spain\'s Rafael Nadal or Argentina\'s David Nalbandian, who are taking the court later in the day in the other quarter-final. The women\'s semi-finals were scheduled for the night session, with world number one Victoria Azarenka facing Angelique Kerber of Germany and second seed Maria Sharapova taking on Serb Ana Ivanovic. Federer needed just 69 minutes to dispatch del Potro, despite a marathon first game that lasted 11 minutes thanks to a problem with the video replay. Federer put on an impressive serving display, hitting a 126 mph ace to get to match point. He then clinched the win when del Potro hammered a forehand into the net. The first set began and ended with video challenges that benefited Federer. In the opening game del Potro tried to challenge a call on Federer\'s serve by asking for a video review on the Hawkeye system. The serve was called in but del Potro thought it was out. When the Hawkeye review system didn\'t work, chair umpire Mohamed Lahyani of Sweden allowed the original call to stand which upset del Potro. \"It was clearly out and the machine didn\'t work,\" del Potro said. \"The chair told me he made a mistake.\" Federer said it was unfortunate but didn\'t think the failed challenge by del Potro had an effect on the outcome. \"I thought it was funny he was getting so upset,\" Federer said. \"It was a tough call for him but I don\'t think it had an effect on the match.\" ATP Tour officials said the problem with the replay came from a dropped Internet connection. \"If Hawkeye does not have the data per ATP rules, the original call stands. We understand there was a loss of the Internet and the data could not be provided,\" the ATP Tour said in a statement. The Hawkeye replay was involved the final game of the first set as well. Federer served and it was called out but he challenged and the replay -- which was working again -- showed it was in. Upon hearing the verdict, del Potro walked towards the video board, turned his racket around and pretended to shoot it.