Two of the top three ranked Americans on the WTA Tour already have been eliminated at the Family Circle Cup.

Vania King lost Tuesday morning to Yanina Wickmayer of Belgium, 6-4, 6-3. King is ranked No. 53. No. 33-ranked Christina McHale was upset Monday, losing to Canada’s Aleksandra Wozniak.

But both Williams sisters are in action today on Daniel Island. Venus and Serena rarely play in the same non-Grand Slam tournaments. They have appeared in the same Family Circle Cup only twice before, in 2004 and in 2007 (Serena was forced to withdraw with injuries in both of those tournaments).

Unseeded Venus Williams won the Family Circle Cup singles title in 2004. She is playing Iveta Benesova in the noon match on Stadium Court. No. 10-ranked Serena Williams, the 2008 Family Circle Cup champion, plays tonight against 2011 runner-up Elena Vesnina at 7 p.m.

Reach Gene Sapakoff at or on Twitter @sapakoff.