BERLIN (AP) — Serena Williams 17-match winning streak ended Friday with a 2-6, 6-1, 7-6 (5) loss to Dinara Safina in the German Open quarterfinals.

The 17th-ranked Russian pressured Williams' backhand, the same tactic that worked a day earlier in an upset of top-ranked Justine Henin.

"It's not like I played my best and lost, it could be worse," Williams said. "I can sit here and name 50 things I could do better."

Also, in Rome, Roger Federer lost again, falling to 27th-ranked Radek Stepanek 7-6 (4), 7-6 (7) Friday in the Rome Masters quarterfinals.

Also losing was eighth-seeded American James Blake, who was defeated 6-7 (5), 7-6 (5), 6-1 by Stanislas Wawrinka.