Roberta Vinci is 32 years old. She has never been to a Slam semifinal in singles before today at the US Open.

Serena Williams is 33 years old. She has been to 27 Grand Slam semifinals before today. She is widely regarded as one of the greatest women’s tennis players of all time. Serena is one Slam short of 22 career Slams, which would tie Steffi Graf for #2 all-time. She was also just two matches away from being the first Calendar Year Grand Slam winner tennis has seen since 1988.

None of that mattered when the two stepped onto court today, though. Williams was expected to easily defeat her opponent. Or, more accurately, as easily as she has made the rest of this Grand Slam chase even possible.

Serena has been anything but dominant in Slams this year. She has had numerous slow starts and been pushed to a third set over ten times in her calendar Slam bid. But whenever push came to shove, Serena upped her level and ended the challenge. No one has been able to finish a match against her because Serena pushed her level of play to a place that no one else could match. Only one player, Heather Watson in Wimbledon, really even had a chance to close out a match. Serena was just that dominant when it all clicked.

Until today, that is. On this US Open semifinal Friday, with both women’s semifinals delayed due to torrential rain all evening yesterday, Roberta Vinci finally had the answers.

The match didn’t start easy. Serena won the first set without much trouble and everyone expected that Vinci, who is not a power player, would not be able to keep up. Finesse and defensive players usually struggle against Serena, who can just hit through whatever her opponents throw at them.

It was the second set that saw the momentum move to the unseeded player. Breaking Williams. the Italian was playing inspired tennis, which saw the American commit more unforced errors than Vinci did. Taking a set from the World #1 for the very first time, Vinci was full of belief as she took the set 6-4 to force a deciding set.

The Italian was not letting this up and continued in this vein taking the opportunities to break Williams in the final set. Williams broke first, though, and it looked like another Houdini comeback from the American.

Vinci had even more answers, though, utilizing every skill she had. She forced Serena to hit extra shot after extra shot and managed to lace winners with unexpected power when the occasion called for it. She broke again for a 4-3 lead, using one of the points of the year to force deuce in that game, and then it was only two service holds between her and history.

A nervy first game saw numerous deuces and several double faults, but Vinci saved the break points and took the match. After a Serena hold, Vinci needed to hang on to her nerve for one more game. She did it without trouble, though, and the Italian Slam champion in doubles is now a Slam finalist in singles as well. Her compatriot Flavia Pennetta awaits in an all-Italian US Open final.

Vinci was clearly overwhelmed by emotion at the occasion of winning this match. She kept her good cheer, though, even apologizing to the crowd for beating their home favorite.

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(Editor’s Note: Glenys Furness assisted in the writing of this article.)

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