Osaka was 'a little bit sad' about US Open final boos

Serena Williams' controversial US Open final defeat to Naomi Osaka was met with boos, saddening the 20-year-old.

Naomi Osaka (L) is comforted by Serena Williams (R) after the US Open final.

Naomi Osaka admitted she was "a little bit sad" her US Open triumph ended in boos after Serena Williams was embroiled in a controversial row with the umpire.

Williams was initially angered at being issued a code violation by umpire Carlos Ramos after a gesture from Patrick Mouratoglou in the player's box was deemed to be coaching, contravening grand slam rules that do not apply on the WTA Tour.

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The American was then handed a point penalty for smashing her racquet as she trailed in the second set and, after calling Ramos a "liar" and a "thief", she was docked a game.

An outraged Williams claimed she was being treated differently to male players while boos rang down from the stands of Arthur Ashe Stadium, before continuing the match in tears.

Osaka kept her composure to complete a 6-2, 6-4 triumph, but the start of the trophy presentation was met with further jeers, resulting in Japan's first major champion crying and apologising to spectators.

"I felt a little bit sad because I wasn't really sure if [the crowd] were booing at me or if it wasn't the outcome that they wanted," Osaka said of that moment on NBC's Today .

"I also could sympathise because I've been a fan of Serena my whole life and I knew how badly the crowd wanted her to win. I don't know, I was just really emotional up there.

"I felt like everyone was sort of unhappy up there and I know that it wasn't really... the ending wasn't what people wanted it to be.

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"In my dreams, I won in a very competitive match, so I don't know, I just felt very emotional and I felt like I had to apologise."

Williams, who missed a chance to claim a record-equalling 24th Grand Slam singles title, refused to answer questions during the presentations but asked the crowd to stop booing and congratulate Osaka in her moment of glory.

"I felt really happy because she knew I was crying and she was saying some things and it just made me happy overall," added Osaka.