Isner was down a set and two breaks to Mikhail Youzhny, and the tall American was seemingly headed out of the Open in quick fashion.

But Isner, down 5-1 in the second, steadied his big serve and reeled off five straight games, then pulled out a second-set tiebreak 9-7, on his fifth set point.

Isner, who made international tennis news with his 70-68 fifth-set win over Nicholas Mahut at Wimbledon but made his first real splash by beating Andy Roddick in the third round here at night last year -- in a fifth-set tiebreak -- will need to be far steadier to overtake Youzhny, the 12th seed, who is as consistent as they come on the men's tour.

The winner faces Tommy Robredo in the round of 16.

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