Haase didn't face a break point and won when Fognini double-faulted for the second time. Haase will next play top-seeded Jo-Wilfried Tsonga of France or Dominic Thiem of Austria.
Eighth-seeded Lukas Rosol of Czech Republic beat 176th-ranked qualifier Ruben Bemelmans of Belgium 6-3, 1-6, 6-3. Rosol will be playing in his second career semifinal and first since winning his maiden title in Bucharest, Romania, in April.
Rosol will face Tommy Haas in the semifinals. The second-seeded Haas defeated Radek Stepanek, 7-6 (10), 6-3, in the quarterfinals.