Defending champion and 2nd seed Caroline Wozniacki had to play her semifinal match against 3rd seed Flavia Pennetta on an indoor court at Yale when it became obvious that the rain in New Haven was not going to stop. Only 300 spectators could fit, and a tin scoreboard was used. Wozniacki defeated Los Angeles champion Pennetta 6-4, 6-1.
The other semifinal, also played indoors, featured 8th seed Amelie Mauresmo and Elena Vesnina. Vesnina defeated Mauresmo 5-7, 6-1, 6-2.
Because of the rain delay, neither the U.S.'s ESPN2 or Tennis TV broadcast the matches, and the electronic scoreboard was down, so I have no idea what actually happened in either match, though I've been busy making some reasonable guesses, especially about the second match.
Wozniacki has a 2-1 record against Vesnina, and on hard courts, a 1-1 record. A tiebreaker in Wozniacki's favor gave the Pilot Pen defending champion a win over the Russian in the semifinals of the 2009 Ponte Vedra Beach tournament (won by Wozniacki), a clay court event. Earlier this year, Vesnina defeated Wozniacki in three sets on a hard court in Auckland.
In doubles, top seeds Nuria Llagostera Vives and Maria Jose Martinez Sanchez defeated Jill Craybas and Lisa Raymond, and will play Iveta Benesova and Lucie Hradecka in the final.