YEREVAN, SEPTEMBER 6, ARMENPRESS. Naomi Osaka won the US Open after an angry Serena Williams accused the umpire of being a "thief", BBC reports.

Serena Williams was given a penalty for her outburst, which followed racquet smashing and another code violation as Osaka won 6-2 6-4 in New York.

Osaka, 20, kept her focus to become the first Japanese to win a Grand Slam.

Williams refused to shake hands with umpire Carlos Ramos after the match.

Williams, 36, graciously congratulated Osaka at the net.

"I'm sorry it had to end like this," a crying Osaka said.

Williams later accused the umpire of sexism, saying: "He's never taken a game from a man because they said 'thief'."

Edited and translated by Stepan Kocharyan