TUCSON, Ariz. - As Rachel Alexandra rocketed through Belmont's long stretch last Saturday, en route to another runaway victory and destroying records set by the immortal Ruffian 34 years ago, it became apparent that those watching might be seeing the greatest filly of all time.\nShe may prove that later this summer, perhaps beating colts in the Haskell at Monmouth or Travers at Saratoga. Zenyatta will make an exceptional race and interesting test if that meeting materializes, but there are two full years between them and almost two full seconds between their performances at 1 1/8 miles last weekend. Eleven wins in California do not equate to winning the Preakness against the best colts of her generation.\nWhile this drama unfolds, there is a truly bizarre case in harness racing involving one of the nation's top pacing fillies who turned out to be a colt. The case is so strange that it intrigued even the skilled hands at the University of Pennsylvania's New Bolton Center.\nThe pacer's name is Martha Maxine, and she/he had won 5 of 11 races and $249,975 this year and 13 of 20 and $193,891 last year, before a post-race anabolic steroid test revealed abnormally high readings for the male hormone testosterone. A model of consistency, the pacer finished first, second, or third 10 times in the 11 starts this year and 19 times first, second, or third in 20 starts last year, earning $451,815 racing against - and beating - the best fillies in the sport.\nOn the strength of the anabolic steroid test findings, Martha Maxine wound up at the clinic of New Jersey veterinarian Dr. Patricia Hogan. Hogan works with both harness horses and Thoroughbreds and is well known in both sports. She is married to a top harness trainer, Ed Lohmeyer.\nHogan quickly determined that Martha Maxine had ambiguous external genitalia, indicating an intersex condition, and recommended further testing at New Bolton. There, the pacer underwent rigorous tests of blood, hair, genitalia, endocrine, ultrasound of abdominal contents, exposure and responses to mares in laboratory and pasture, overall behavior, and chromosome evaluation. It was determined that Martha Maxine was a male pseudohermaphrodite.\nFollowing that evidence, New Bolton informed the trainer - Erv Miller of Illinois, the leading harness racing trainer in the United States last year - that Martha Maxine was not a filly or mare, but a male horse.\nOn the basis of these findings, the United States Trotting Association, breed registry of the sport, notified Miller and Martha Maxine's owners and other agencies that the horse was reclassified as a male.\nMartha Maxine immediately became ineligible for filly and mare races and now may race only against male horses and geldings, or in open events. Her registration papers and past performances must include the line "Martha Maxine has been determined to be a genetic male and is not suitable for breeding purposes." The nearly half-million she has won remains with her owners, the Ervin Miller stable in Springfield, Ill., Tony Alagna of Sorrento, Fla., and Brittany Farms of Versailles, Ky., one of the major harness racing breeding operations in the world.\nAn interesting sidebar to the story: Before the official discovery of Martha Maxine's gender, a close relative, the former Arizona Helen, also raced and won $169,546 as a pacing filly. After winning two races at Harrah's Chester Casino and Racetrack just south of Philadelphia last winter, she too tested positive for high testosterone levels. Her trainer, Rich Belach, insisted she had not been given steroids.\nLike Martha Maxine later, she wound up first at Hogan's clinic for examination and then was sent on to New Bolton, where her high testosterone levels were explained. While she had the outward appearance of a female, ultrasound examination revealed no uterus or ovaries but two internal gonads having the appearance of testicles. New Bolton said Arizona Helen is a genetic male with incomplete masculinization of the external genitalia. He too has been reclassified by the USTA and must race against males and geldings, or in open company, with a notation that he is unsuitable for breeding.\nArizona Helen's dam, Bret's Excellence, was a daughter of the world champion Bret Hanover. Bret's Excellence is the second dam of Martha Maxine. Arizona Helen's grandsire, Abercrombie, one of the sport's greatest sires, also is the great grandsire of Martha Maxine. Although the condition of these two is rare, and scientists do not know the cause of intersex horses, it appears it is an inheritable defect. The New Bolton vets called the cases "unusual and interesting." No word that the owners and trainers agree.