They played one another for the first time at the Australian Open in 1998, and Venus was the winner. In quarterfinal contests, Venus was 2-0, having earned victories at the Italian Open 6-4, 6-2 in 1998 and 6-1, 7-6 at Miami in 2005. Serena has been the best when matches have gone to three sets, leading 4-1.

Since 2000, they have played three times at the U.S. Open. Venus was the tournament champion in 2001. Serena was the winner the next year. In 2005, Venus defeated Serena in the round of 16.

Family match-ups are not only difficult to play, they are always filled with emotion. No matter how good the players are, the contests usually aren't of the highest quality. Family means more than winning. It's almost as if sisters would like to share the victory.

Looking at sister-sister battles other than Serena and Venus, Katernya Bondarenko, who is two years older than Alona, leads their series 3-2, but Alona won their only three-setter in the final at Bali 2-6, 6-2, 6-4 in 2004.

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Manuela Maleeva-Fragniere, who is two years older than Katerina Maleeva, dominated their rivalry 8-1, the only loss coming when she had to retire at the Canadian Open in 1991. Being eight years older than younger sister Maggie Maleeva, it's not surprising that she was 2-0 in their showdowns, one of which was at the U.S. Open in 1992. Following the "older is better than the younger" theme, Katerina was 4-0 against Maggie, including straight set wins in New York in 1991 and 1993.

Kathy Jordan, another who is two years older, never played her sister Barbara when they were on the circuit back in the 1980s.

As hard as it would have been to sit through the two hour and 25 minute match, I'm sure that Richard and Oracene were happy with the way the sisters played. Serena has her game together and she has a good shot at winning her third U.S. Open title, and first in six years.