Top-seeded Jo-Wilfried Tsonga also reached the Stockholm quarterfinals.

STOCKHOLM (AP) -- Tomas Berdych reached the quarterfinals at the Stockholm Open with a 6-1, 6-4 win over Estonia's Jurgen Zopp on Thursday.

Berdych broke Zopp's serve three times in a victory that took only 71 minutes. The Czech will next face Russia's Mikhail Youzhny and remains in line to qualify for the season-ending ATP World Tour Finals in London.

Top seed Jo-Wilfried Tsonga, also hoping to qualify for London, advanced with a 6-3, 7-6 (6) win over Go Soeda of Japan. The Frenchman faces Sergiy Stakhovsky of Ukraine in the quarterfinals after Stakhovsky beat Spain's Feliciano Lopez, 7-6 (5), 7-5.

Marcos Baghdatis of Cyprus advanced when Alejandro Falla of Colombia retired because of a left foot injury while trailing 6-0, 3-0. Baghdatis faces Lithuania's Ricardas Berankis in the quarterfinals.

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