Songbird’s most ambitious fans won’t get to see their filly run against colts in the $1 million Santa Anita Derby on Saturday, but at least she will be on the undercard. If this sounds wrong, you’re right. Madonna does not open for Avril Lavigne. You don’t advertise Bruno Mars, then mention in the small type that Springsteen will play a set. No one ever heard, “Ladies and gentlemen, I know you’ve all paid to hear the Dave Clark Five tonight, but first, here’s Elvis!” Unless you are the owner of one of the colts running in the Santa Anita Derby – and good luck to all – it is a matter of record that the most exciting 3-year-old in California right now is a filly. Ask around. Songbird has ignited the imagination like no female since Zenyatta. Her every move is documented like the tides. She has run six times and won six times, never troubled, never touched. When Songbird began to draw off in the stretch of the Las Virgenes Stakes at Santa Anita on Feb. 6, her first start of the year, the standing ovation began at the eighth pole and did not let up until she and Mike Smith joined owner Rick Porter and trainer Jerry Hollendorfer in the winner’s circle. The subsequent Santa Ysabel Stakes was little more than a paid workout, and the reaction was no less enthusiastic, although it had become tinged with the fervent wish that Songbird soon would begin to beat up on the boys. So far, her people have taken the path of least resistance … and most sense. Still three weeks shy of her third birthday, Songbird’s main target of the spring is the Kentucky Oaks, which is why they are running Saturday in the $400,000 Santa Anita Oaks instead of half an hour later in the local Derby. Even so, comparisons to her male contemporaries are inevitable. Songbird might not be running in Saturday’s Derby, but she definitely will be running against it. “I guarantee there will be a time,” said Tom McGreevy, Porter’s bloodstock adviser. “Rick wants to run her at 4 and 5 because he’s not in the business to sell her. There will be a lot of opportunities down the road for her to make history.” McGreevy was the guy who sifted through the herd at the 2014 Fasig-Tipton August select yearling sale at Saratoga and came up with the dark bay daughter of Medaglia d’Oro with the white stockings, star, and dribbling blaze. Porter’s $400,000 took care of the rest. McGreevy is a Penn State graduate and Vietnam vet who tried his hand at training but discovered his talents were best suited to the quest for the best possible Thoroughbred racehorse. “That’s what challenges me – the hunt,” he said. “And what I think really helped me the most over the years is understanding the conformation of the horse, how the parts are supposed to fit together and what their purposes are.” Whether McGreevy knew it or not, his college days were preparing him for the moments when he recommended the purchase of yearlings who turned out to be Midnight Lute, Havre de Grace, and Songbird, all champions. He not only earned a degree in animal science, he also moonlighted as a livestock judge, which is not as simple as it sounds. “We judged pigs, cattle, sheep, horses,” he said. “It really helped develop your eye. In the morning, we’d have 10 different classes with four animals in each, then in the afternoon, you had to place them 1-2-3-4 and tell the official judge why. You couldn’t just say, ‘He’s a pretty horse.’ ” Or sheep, or pig. “Yes, there are distinct things to look for in a pig,” McGreevy said, taking the bait. “But it’s been a long time, and I really can’t remember what they are.” McGreevy insists that he never goes deeper than the sire of a sales horse on the catalog page, and then only to soften the impact of any conformational idiosyncracies that might be typical of the stallion’s offspring. In his search for those special physical specimens, he does not want to be distracted by black type and fancy families. Anyway, it’s usually the pedigree that sends prices through the roof. “As they go through that first Keeneland book, it still amazes me to see them going for $300,000, $500,000, $700,000,” McGreevy said. “Then, later, you see Grade 1 races come up with small fields and you wonder, ‘Wow, where are they? Isn’t this what you bought them for?’ ” The science is far from exact, and picking out a gem like Songbird gives any bloodstock agent bragging rights for as long as people will listen. “Songbird has turned out to be pretty much what I saw as a yearling,” McGreevy said. “After seeing thousands of young horses, she’s an example of what you’re looking for, and one of the most important things is their demeanor at the sale. “Most of the good horses figure things out pretty quickly,” McGreevy said. “They’re just more confident in their presence in the world. And that translates later on. When they get to the races, they’ll walk into the paddock like, ‘Here I am. What you got?’ That’s Songbird. She was all that. “And yet she is so kind,” McGreevy added. “The day after the Breeders’ Cup at Keeneland, my wife and daughter and I went back to the barn. A lot of horses, after they go through all that, just stay in the back of their stall with their head down. She was at the front of her stall with her head out, looking for someone to pet her, give her a carrot.” Songbird is one of nine yearlings Porter bought that year on McGreevy’s recommendation. And while the rest have yet to do anything special, anyone would take one Songbird in a heartbeat and not worry about the other eight. McGreevy was asked if he recalled the name of the unlucky underbidder. He laughed. “The last I heard, there was about 10 or 12 of them,” he said. A previous version of this article misstated the 2014 sale at which Songbird was purchased as a yearling. It was the Fasig-Tipton August select yearling sale at Saratoga, not the Keeneland September yearling sale.