Venus Williams and Sara Errani may have engaged in the most compelling match of the 2014 U.S. Open. Unfortunately, a lack of sportsmanship from Errani diminished the legacy of this two-hour classic Friday.

In an odd sequence, Errani won the first set of the third-round match 6-0 while Williams took the second 6-0. After the bagel exchange, Williams had a chance to serve out the match at 5-3 in the third. But a crucial double fault opened the door for Errani, who rallied and won on a tiebreaker.

The mostly American crowd had been forcefully pro-Venus during the wild match, but when Errani took the final point, fans gave a standing ovation to both players.

Errani, 27, did not embrace the calling. One could make the argument there is a cultural barrier, but Errani's post-match actions suggested she was happy to stick it to the American crowd.

After pumping her chest and shaking Williams' hand, Errani cupped her hand to her ear. In all languages, this is a sign of pointing out a crowd's noise level. For a home athlete, this is usually to make them louder. For a visitor, it can be taken as a mockery of the noise level.

Errani, who was the higher seed in the match (No. 13 vs. No. 19), continued to holler at the audience, wagging a finger at the crowd and raising it to her mouth, telling the Americans to be quiet. In Errani's defense, this is a motion she has done before, as can be seen in highlights from this year's French Open. Given the venue, Errani could have held back. In the United States, such an act is taken as poor sportsmanship (with the possible exception of Dikembe Mutombo).

Sara Errani Mocks U.S. Open Fans

Asked what message she was sending with those demonstrative gestures, Errani said she was nervous, particularly after pulling even at 5-5 in the tiebreak:

"Five-all in the tiebreak, I heard the crowd. Never hear the crowd like that strong. I was shaking for the crowd. [It] was unbelievable good. I think I will remember that moment forever. Of course, in the point after, I was nervous. I was like now you don't scream, like if they didn't scream. But of course the crowd was for her, totally for her. I don't know why I did like that."

Errani entered the match 0-3 against Williams, a seven-time Grand Slam champion. Errani is also 0-7 against Serena Williams, including semifinal losses at the 2012 U.S. Open and the 2013 French Open.

Errani, who called her win "unbelievable," said was not mad with the New York fans.

"I was with the tension, with the adrenaline in the body, so I was just -- I don't know," Errani said. "I don't know how to explain it."

That could be a language limitation for Errani, who is Italian. But Errani is also an established WTA professional. She has been ranked as high as No. 5 in the world and is currently No. 15. She has enough experience to fight her way out of a hole even in the trenches of Flushing Meadows.

When it came to talking about the crowd on Venus' side, she said she did not prepare for the Venus fans, but rather just Williams' game.

"I just was thinking about that Venus is a great player -- unbelievable player," she said. "Every time I play against her, she won against me very easily. I thought I had to make my level higher, try to be much more aggressive than any time, and try to keep focus on every point.

"The crowd was amazing. Even if it was not for me, it was for her. But to hear that scream of all the people I think I will always remember."

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