Isner loses to Harrison in Sydney
The exit of Isner, who was promoted to the No. 1 seed after Jo-Wilfried Tsonga and Richard Gasquet withdrew, followed two more injury withdrawals: No. 2 and 2011 Sydney champion Giles Simon (neck) and No. 6 Radek Stepanek (back).
Isner, who withdrew from the Hopman Cup mixed team competition in Perth last week with a right knee injury, lasted 71 minutes against No. 64-ranked Harrison.
The Australian Open starts Monday, leaving injured players little time to prepare for the season's first major.
Copyright 2013 by The Associated Press
This story is from ESPN.com's automated news wire. Wire index
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