Berlin: Dinara Safina ended Serena Williams’s 17-match winning streak with a 2-6, 6-1, 7-6 (5) victory on Friday to reach the German Open semi-finals.

The 17th-ranked Russian kept pressuring Serena’s backhand, the same tactic that worked a day earlier in an upset of top-ranked Justine Henin.

Both players held serve throughout the final set, before Serena let a 4-3 lead in the tiebreaker slip away and sent a forehand long and wide to end the two-hour match.

Serena, chasing a fourth straight title, appeared poised to improve on a 21-1 record this year without trouble until Safina’s hard shots began to land in the second set.

Serena was the 10th top-10 victim for the 22-year-old Safina. Safina broke twice to start the second set, whipping a shot past Serena at the net to take a 4-0 lead.

She will face Victoria Azarenka in the semi-final, after the Belarussian ousted 15th-seeded Alona Bondarenko 7-6 (2), 6-2. (AP)