Although the connections of Horse of the Year Rachel Alexandra chose to pass on the Grade I Apple Blossom Invitational today, the show must go on - and unbeaten champion Zenyatta is still at Oaklawn Park to attempt to enhance her legacy.

A victory by the two-time Eclipse champion older female would improve her record to a perfect 16-for-16 lifetime, matching the accomplishments of Citation and Cigar for consecutive victories at an elite level. Her streak includes victories in the 2008 Breeders' Cup Ladies Classic and the 2009 Breeders' Cup Classic - making her the only female ever to win one of North America's biggest prizes. Most recently, the daughter of Street Cry overcame traffic trouble to win the Santa Margarita in her 6-year-old debut on March 13.

Zenyatta captured the 2008 edition of the Apple Blossom, defeating then-reigning champion older female Ginger Punch, in her only start outside of California and her only start on a conventional dirt surface. She arrived in Arkansas on Tuesday for a repeat engagement.

With the purse, which would have been $5 million of both star females had started, reverting to its original $500,000, only four rivals could be convinced to take on Zenyatta. The chief challengers figure to be the 4-year-old fillies Just Jenda and War Echo. Just Jenda, who races for Cindy and Larry Jones, won the Tiffany Lass, Honeybee, Serena's Song and Monmouth Oaks last year. War Echo, a Steve Asmussen-trained half-sister to Grade I winner Pyro, won the Silverbulleyday and the Daily Racing Form Distaff Stakes in 2009.

Expected pacesetter Be Fair won the off-the-turf Lake George Stakes at Saratoga last summer. Longshot Taptam rounds out the field.