Jan. 16 Owner Jerry Moss brings Zenyatta out of retirement and says she will begin her 2010 campaign in the Santa Margarita on March 13. Jan. 18 Rachel Alexandra beats out Zenyatta for the 2009 Horse of the Year title, earning 130 first-place votes to 99 for Zenyatta. Feb. 4 Oaklawn president Charles Cella announces he will raise the purse of the April 3 Apple Blossom to $5 million if Rachel Alexandra and Zenyatta both start. Feb. 10 Jess Jackson, the owner of Rachel Alexandra, says he will not run her in the Apple Blossom because the date of the race is too early. Feb. 11 Cella says Jackson and Moss have agreed to run Rachel Alexandra and Zenyatta in the Apple Blossom on a new date, April 9. March 13 In their 2010 debuts, Zenyatta rallies to a 1 1/4-length win in the Santa Margarita, but Rachel Alexandra is outdueled in a three-quarter-length loss to Zardana in the New Orleans Ladies. March 14 Jackson announces that Rachel Alexandra will not run in the Apple Blossom. April 9 Zenyatta easily wins the Apple Blossom, cruising by 4 1/4 lengths over four opponents. Watch Replay >> Sept. 28 Rachel Alexandra is retired after winning two of her five 2010 starts. Her rivalry with Zenyatta was never settled on the track. YEAR IN REVIEW: Jay Privman's 2010 recap | Dan Illman's highs and lows DRF WEEKEND: Handicapping roundups, Q&A with jockey Greta Kuntzweiler