At the 2009 French Open, who ended Serena Williams's 18-match Grand Slam winning streak?

At the 2009 French Open, Svetlana Kuznetsova ended Serena Williams’s 18-match Grand Slam winning streak.

Kuznetsova, the seventh seed, beat the second-seeded Williams in a dramatic quarterfinal, winning 7–6, 5–7, 7–5. Williams had won the 2008 US Open and the 2009 Australian Open, so she entered Paris seeking a third consecutive major title. Kuznetsova’s victory stopped that run before the semifinals.

The match turned on small margins. Williams had a set point in the opening set and led 3–1 in the third, but Kuznetsova recovered and broke Williams while serving for the match. The Russian then continued through the draw, defeating Samantha Stosur in the semifinal and Dinara Safina in the final.

A common mix-up is to associate the loss with another Russian star from that era. Elena Dementieva and Dinara Safina were prominent rivals, but neither ended this particular streak. Kuznetsova’s win was especially significant because she went on to claim her second Grand Slam singles title.