Janko Tipsarevic received treatment on his injured foot injury and called it quits when trailing 6-2, 5-1.
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Eighth-seeded Janko Tipsarevic retired from his fourth-round match at the Australian Open with an injured left foot while trailing Nicolas Almagro 6-2, 5-1 on Sunday.

The 10th-seeded Almagro advanced to a quarterfinal against fellow Spaniard David Ferrer, who beat Japan's Kei Nishikori in straight sets.

Tipsarevic said he injured the foot while changing directions during a rally late in the seventh game of the first set, and could barely walk on it afterward.

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