The $5 million race between leading ladies Rachel Alexandra and Zenyatta is off, leaving unbeaten Zenyatta to take on others next month in Arkansas.

Rachel Alexandra's owner, Jess Jackson, said Sunday that his Horse of the Year is not in top form after her defeat in the New Orleans Ladies at the Fair Grounds. So the highly anticipated showdown between racing's top stars will not occur April 9 in the Apple Blossom Invitational at Oaklawn Park.

"Yesterday's race, while a disappointment, helped us define Rachel Alexandra's racing condition," Jackson said in a statement. "While she is healthy, just as I had anticipated, she is not in top form. Therefore, I decided today she will not be going" to Oaklawn for the race.

Rachel Alexandra and Zenyatta were making their first starts of the year Saturday in what were supposed to be prep races for next month's event, which saw its purse raised to $5 million from $500,000 only if both horses started.

That won't happen now, but Zenyatta's co-owner Jerry Moss said his 6-year-old mare will still run as scheduled.

"We're disappointed that we're not going to be able to face each other in the Apple Blossom," he said Sunday from his California home. "Hopefully, we can meet down the line. We respect both Steve (Asmussen) and Mr. Jackson as horsemen and they're going to do what's right for their horse. That's all anybody could ask for."

While Zenyatta did her part in winning the Santa Margarita Handicap at Santa Anita, Rachel Alexandra was not as fortunate in her 4-year-old debut. She was beaten by Zenyatta's stablemate, Zardana. Both mares are trained by John Shirreffs.

Rachel Alexandra, trained by Asmussen, had seven timed workouts leading to Saturday's race, but weather problems may have compromised her training schedule.

"Steve and I discussed this fully and we now regret we tried to accelerate her training in order to meet the Apple Blossom schedule," Jackson said. "We have a whole season before us to help define her greatness. She will tell us when her next race will be."

Zenyatta came into the Santa Margarita off a four-month rest. Jerry and Ann Moss had intended for her to retire and begin a breeding career after she became the first female to beat the boys and win the $5 million Breeders' Cup Classic in November.

But they changed their minds in January and put her back into training.

Asked if she is better now than she was last year, Shirreffs said, "How can you be better than perfect?"