Naomi Osaka was upset by an 18-year-old in the third round of the U.S. Open.
Canadian Leylah Fernandez, who is ranked 73 in the world, beat Osaka Friday night in three sets.
Osaka served for the match in the second set, but Fernandez broke Osaka to force a tiebreak, which she won 7-2.
Fernandez continued to put pressure on Osaka, who started to get visibly frustrated.
Osaka threw her racket several times during the match and got a warning for hitting a ball into the stands.
Fernandez said she didn't focus on Osaka and worried about what she had to do to win the match.
She closed out the match, 5-7, 7-6, 6-4, when Osaka hit a forehand wide on match point.
Fighting tears, Osaka said after the match that she didn't know when she was going to play her next match.