Roberta Vinci planning to watch clash between Serena and Venus Williams

Roberta Vinci has insisted that she has no preference regarding who she faces in the US Open semi-finals.

After beating Kristina Mladenovic in three sets, Vinci will face either Serena or Venus Williams, but while the Italian admits that she will watch the match, she has revealed that she is happy to face either of the Americans.

The 32-year-old said after the match: "It will be a tough match. It is not an easy match to play against your sister and Serena has a lot of pressure.

"I will watch the match but whether it is Serena or Venus, I am just so happy to have reached the semi-final."

Vinci has lost all four of her matches with Serena, while she has also failed to defeat Venus in three attempts.