AUBURN, Wash. -- My Untamed Heart, one of the fastest horses at Emerald Downs through the first 12 days of the meeting, headlines Saturday’s feature race, a first-level optional $15,000 claimer for fillies and mares at six furlongs. Preakness Day festivities begin with the first live race at 2 p.m. Pacific. Animal Kingdom’s bid for the second leg of the Triple Crown is scheduled for a 3:16 post time, between the third and fourth races on Emerald’s nine-race card, and the feature is race 8.My Untamed Heart probably couldn’t get the demanding Preakness distance; she faded to finish a distant seventh in the 2010 Washington Oaks in her only try around two turns. But the Vann Belvoir-trained 4-year-old My Untamed Heart has been a terror sprinting, winning three times in five starts. In her last outing April 29, My Untamed Heart hooked up in a torrid speed duel with Cliff’s Secret before giving ground in the final yards to miss by a length. Cliff’s Secret ran the 5 1/2 furlongs in 1:02.33 after she and My Untamed Heart zipped through a half mile in 43.97 seconds and five furlongs in 55.92. Cliff’s Secret was assigned an 89 Beyer Speed Figure for her effort, the fastest race at the meeting. My Untamed Heart got an 86 Beyer, still second-fastest through the meet’s first 130 races. Belvoir said he thought about running My Untamed Heart in the Hastings Handicap last Sunday but concluded that an extra week of low-intensity training might prevent her from “bouncing” in her next start. She will face a softer group Saturday, though at least two entrants, All the Rage and Smoke Rise, have reasonable chances to upend the favorite.All the Rage climbed the claiming ladder last summer, beginning the Emerald meet in a $3,500 claimer and rising as high as first-level allowance company before dropping to finish second for $10,000 in her final start. She looked sharp in her 2011 debut, leading all the way to take a $12,500 claimer by three-quarters of a length and earn a 72 Beyer, but will need to improve yet again, and perhaps get some regression from My Untamed Heart, to post the upset. While All the Rage has plenty of experience (27 starts), Smoke Rise is just getting started. Unraced at 2 and 3, she won her debut at Emerald on April 23, coming from just off the pace to win a 5 1/2-furlong maiden race by five lengths. She got a 72 Beyer while hinting that she’s capable of more.