Roberta Vinci def. Serena Williams – 2015 US Open:
Arguably the greatest women’s tennis player of all-time, Williams was on a journey to become the first female since Steffi Graf to lock up a Grand Slam in one year.
That all changed when she met Vinci in the semifinals of the 2015 US Open. There, Vinci outlasted No. 1-ranked Williams in three sets by a score of 2-6, 6-4, and 6-4.
She obviously never became the transcendent star Williams is, but along with partner Sara Errani, Vinci was one of only five couples to complete a career Grand Slam in doubles competition. She’ll always be known for her historic upset of Williams.