Wednesday September 9th, 2015

Following her victory over Venus Williams in the U.S. Open quarterfinals on Tuesday night, Serena Williams posted a heartfelt Instagram dedicated to her sister.

“She has my heart,” the No. 1 seed in U.S. Open women's singles writes about the older Williams, adding that a lifetime with her sister will not be enough.

The sisters faced off in an emotional match, Serena appearing to hold back tears as the third set came to an end and she earned a 6–2, 1–6, 6–3 victory over Venus to advance to the semifinals.

“She's the toughest player I've ever played in my life and the best person I know,” Serena said after the match.

• Serena's difficult win over Venus revealed her need for the Grand Slam

Serena now leads the all-time head-to-head series with 16 wins to Venus's 11. Serena has won three of five meetings against Venus at the U.S. Open.

Serena will face Roberta Vinci in the semifinals on Thursday. The younger Williams sister is looking to win the calendar Grand Slam, a feat that has not been accomplished since Steffi Graf did it in 1988. Serena is also seeking her fifth consecutive Grand Slam title and her fourth straight U.S. Open title.

- Xandria James

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