HOUSTON (AFP) - Germany's Dustin Brown upset top-seeded American John Isner in three sets to reach the quarter-finals of the US men's clay-court championships on Wednesday.
The world No. 101 Brown outlasted the hard-hitting defending champion Isner 6-4, 6-7 (7-9), 7-6 (7-4) on the clay courts at the River Oaks Country Club.
Isner forced a deciding set by winning an extended tie-breaker in the second, but Brown rebounded to claim the final tiebreak. It was his first-ever victory over a top-10 opponent.
Isner, who is ranked ninth in the world, beat Nicolas Almargo in the 2013 final. Brown will next face Sam Querrey in the quarter-finals after the 2010 Houston finalist toppled former champ Lleyton Hewitt of Australia earlier on Wednesday.
Querrey beat seventh-seeded former world number one Hewitt 6-3, 6-4 in just 76 minutes. Hewitt, who is enjoying a resurgence this year, won in Houston back in 2009.