Serena Williams through to 4th round in Australia
Williams, who won last year's Wimbledon and U.S. Open titles, showed no discomfort from the right ankle injury she sustained in the first round.
She'll play her fourth-round match against Maria Kirilenko, who beat Yanina Wickmeyer earlier Saturday.
Williams won six games in a row to end her match with Morita, coming back from a 3-0 deficit after losing her serve with a double-fault on break point in the second game of the second set.
Copyright 2013 by The Associated Press
This story is from ESPN.com's automated news wire. Wire index
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