James Blake reaches Swedish quarters

STOCKHOLM -- American James Blake upset second-seeded Juan Martin del Potro of Argentina 6-4, 6-4 on Wednesday to reach the quarterfinals of the Swedish Open.

South Africa's Kevin Anderson and Milos Raonic of Canada also advanced. Anderson needed three sets to beat 33-year-old Tommy Haas of Germany 6-7 (3), 6-4, 6-4, while Raonic easily defeated Philipp Petzschner of Germany 6-3, 6-3.

In other matches Wednesday, Bernard Tomic of Australia beat Estonia's Jurgen Zopp 7-6 (5), 4-6, 6-0 to reach the second round, and Grigor Dimitrov of Bulgaria defeated American Ryan Sweeting 6-3, 6-1.

Germany's Sebastian Rieschick also advanced to the second round after beating home crowd favorite Michael Ryderstedt of Sweden, 6-4, 3-6, 6-3.