PARIS (AP) -- Simona Halep has lost the first set of her third-round match to Japanese teenager Naomi Osaka 6-4 at the French Open.
Halep's second serve is letting her down. In the third and ninth games, Osaka pounced on weak second serves to break the sixth-seeded Romanian, who reached the French Open final in 2014.
The set saw five breaks of serve.
Osaka, playing in only her second major tournament, reached the third round at this year's Australian Open.
A loss to the 101st-ranked Osaka would be the fourth time in the last five Grand Slam tournaments that Halep has fallen to a player ranked 70 or below.