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Overcoming a mid-match lull and a third-set deficit, Serena Williams won her third French Open title and 20th major singles trophy by beating 13th-seeded Lucie Safarova of the Czech Republic 6-3, 6-7 (2), 6-2 on Saturday.

The top-ranked Williams took the last six games and added to her championships on the red clay of Roland Garros in 2002 and 2013.

She stretched her Grand Slam winning streak to 21 matches, following titles at the U.S. Open last September and Australian Open in January.

Only two women in the century-plus history of Grand Slam tennis have won more major titles than the 33-year-old American: Margaret Smith Court with 24, and Steffi Graf with 22.

This one did not come easily, though, for Williams, who has been dealing with an illness and skipped practice Friday.

She double-faulted 11 times, part of 42 total unforced errors, 25 more than her opponent. In the third set, she fell behind 2-0, was warned by the chair umpire for an audible obscenity and even resorted to hitting one shot left-handed.

Whatever it takes to win, right? No one does that better than Williams, who is 32-1 in 2015, including 12-0 in three-setters.

She is the first woman since Jennifer Capriati in 2001 to win the Australian Open and French Open back-to-back and will head to the grass courts of Wimbledon this month with a chance to extend a bid to do just about the only thing she hasn't accomplished: win a calendar-year Grand Slam.

Her three French Open titles now go alongside six each from the U.S. Open and Australian Open, and five from Wimbledon.

When Saturday's match, which went from a stroll to a struggle, was over, Williams' coach, Patrick Mouratoglou, stood and raised his hands. He held aloft two fingers on his right and made a fist with his left, to symbolize "20."

And to think: Four times in her first six matches over the past two weeks, Williams dropped the opening set before coming back to win, including in Thursday's semifinals, when Williams was lethargic and, Mouratoglou would say afterward, bothered by the flu, a fever and difficulty breathing.

So the most meaningful question leading into the final against Safarova, a 28-year-old lefty with a whip-like forehand who was making her Slam final debut in her 40th major appearance, was this: How healthy would Williams be?