Naomi Osaka, of Japan, holds the trophy after defeating Serena Williams in the women
PHOTO: Adam Hunger/AP
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PHOTO: Ezra Shaw/Getty Images North America/Getty Images
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(CNN) —  

The US Open has fined Serena Williams $17,000 for three code violations during her loss in Saturday’s women’s singles final, the United States Tennis Association said.

Saturday’s match between Williams and Naomi Osaka in New York’s Arthur Ashe Stadium was marred by controversy in the second set after umpire Carlos Ramos penalized Williams a point and then an entire game. Osaka beat Williams in straight sets – 6-2, 6-4 – to win her first Grand Slam title.

Here’s why Serena Williams is calling out sexism

Ramos first issued a warning to Williams after ruling that her coach, Patrick Mouratoglou, gave her hand signals that Ramos said constituted illegal coaching. Williams denied the accusation and could be heard repeatedly demanding an apology from Ramos.

PHOTO: Jaime Lawson/Getty Images North America/Getty Images for USTA
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