Serena Williams: "Venus would have won 15 Grand Slams if we hadn't played against each other".

In a lengthy interview with the New York Times, Serena Williams answered a number of questions on a variety of subjects.

In particular, the American confided in us about her long-standing rivalry with her sister, Venus, and the impact this has had on their respective careers.

She declared: "We had this rule that if we played each other before the final, we had to win the title. I think Venus would have had at least 15 Grand Slam titles if we hadn't played each other. I would have had 30.