Apple failed to convince a US judge to block Samsung Electronics from selling Galaxy smartphones and tablets in the US market, depriving the iPhone and iPad maker of crucial leverage in a global patent battle between the two firms. In a ruling released late on Friday, District Judge Lucy Koh in San Jose, California, denied Apple\'s request for a preliminary injunction against Samsung. The two companies are engaged in a bruising legal battle that includes more than 20 cases in 10 countries as the they jostle for the top spot in the smartphone and tablet markets. Earlier on Friday, an Australian court extended a halt on sales of Samsung\'s latest Galaxy tablet in the country by at least a week, as Apple appeals a ruling that had ended the ban. Apple sued Samsung in the United States in April, saying the South Korean company\'s Galaxy line of mobile phones and tablets \"slavishly\" copies the iPhone and iPad. Article continues below But on Friday Koh rejected Apple\'s bid to ban sales of three smartphone models, as well as the Samsung Tab 10.1. \"It is not clear that an injunction on Samsung\'s accused devices would prevent Apple from being irreparably harmed,\" Koh wrote. Apple spokeswoman Kristin Huguet on Friday referred to previous Apple statements about the case, saying that Samsung\'s \"blatant copying is wrong\". Expectations missed Global tablet sales are expected to explode to more than 50 million this year. Apple, which has sold more than 30 million iPads so far, is expected to continue to dominate the market in the near term. Apple\'s new CEO Tim Cook is under pressure to show he can fill the large shoes of his predecessor, late Silicon Valley titan Steve Jobs. But in his first quarterly result unveiled as permanent CEO, Apple stunned Wall Street, missing expectations for the first time in years.