AUBURN, Wash. - Emerald Downs director of racing Bret Anderson unwrapped the list of nominees for the Grade 3, $300,000 Longacres Mile late Sunday, and by Wednesday morning the original roster of 25 had been pared to fewer than 20 horses with designs on the Northwest's richest race. \nEmerald-based stakes winners Assessment and Atta Boy Roy top the local contingent for the Aug. 16 showcase; Teide, a recent stakes winner at Hastings, is the leading contender from Canada; and Sierra Sunset, one of the nation's leading 3-year-olds last year, headlines a small group from California. \nRuled out early this week were Dakota Phone, a Jerry Hollendorfer-trained 4-year-old who finished fifth in his last start in the Grade 1 Eddie Read Stakes at Del Mar, and Talkin to Mom Roo, a Southern California-based sprinter trained by Ted West for owner Jeffrey Sengara, who won the 1999 Longacres Mile with Budroyale. \nAlso unlikely were Hollendorfer's Crafty Power, who won the Portland Meadows Mile in March, and the Bob Baffert-trained trio of Sangaree, Screen to Screen, and Mayor Marv. \nThe winner of the Longacres Mile is guaranteed a spot in the Breeders' Cup Dirt Mile at Santa Anita on Nov 7. Weights for the Mile will be announced Saturday, and entries will be taken next Wednesday. A maximum of 12 horses can start. \nAtta Boy Roy, who won the 6 1/2-furlong Governor's Handicap July 5 in his most recent start, will have a new rider, trainer Valorie Lund said Wednesday. Ricky Frazier, who leads the jockey standings by a wide margin, will replace Joe Crispin, who was 2 for 2 on Atta Boy Roy this summer. \n"Joe got hurt again and he's had trouble being here," Lund said. "We have to have a rider who's going to be here for the horse. It's the injuries that have cost him the mount, basically. I feel bad about that, but Roy loves Ricky. I've never seen him work better for anybody."\nAtta Boy Roy, who equaled the six-furlong track record of 1:07.40 in an allowance-race victory in early June, has trained brilliantly for the Mile, though the front-running 4-year-old never has won around two turns. \n"He worked six furlongs in [1:10.20] the other day, cruising along as comfortable as can be," Lund said. "We caught him on the gallop going a mile in 1:36, so I think we're ready.\n"It's a deep, deep group. There are a lot of nice horses, but I have a very nice horse and he's absolutely on top of his game. Ricky had his pick of some of the horses that were coming in, and there were some nice ones. That says a lot about our horse."\nSierra Sunset, denied a chance to run in the 2008 Kentucky Derby because of an ankle injury, arrived at Emerald Downs Tuesday and jogged Wednesday morning, trainer Jeff Bonde said. \nSierra Sunset won the Rebel Stakes at Oaklawn Park last April, but an ankle injury revealed itself a couple of days after the race, scrapping Derby plans and sending him to the sidelines for more than a year. He won the 1 1/16-mile Alamedan Handicap at Pleasanton on July 5 in his second start following the layoff. William Antongeorgi will ride Sierra Sunset in the Mile. \n"This is a quality horse," Bonde said. "He ran a huge race at Pleasanton; we didn't have to ask him for his best. He's plenty fit, he's a fresh horse, he's very dangerous in this kind of race. If he can win this and get into the Breeders' Cup, it would make the rest of the year a lot easier."\nTeide, who won the nine-furlong Lieutenant Governor's Handicap at Hastings in his most recent start, will start in the Mile, trainer Dino Condilenios confirmed Wednesday from Vancouver.\n"I'm really happy with the way he's coming up to the race," Condilenios said. "I wouldn't be coming down if I didn't think we had a shot."\nPurchased privately last winter, Teide has won two of his three starts in Canada. He competed primarily in allowance company in New York, Florida and Kentucky prior to the sale. \n"It seems like he's getting bigger, better and stronger," Condilenios said. "He's run at a lot of different tracks, so the short ship won't bother him at all, and he won't have any problem on a mile racetrack because he's such a big horse. We've got a shot, and hopefully the tigers don't all show up."\nThe Mile could take on a decidedly different look if Awesome Gem joins the field. A fast-closing second in the Eddie Read at Del Mar, he has finished second in three Grade 1 stakes and was third behind Curlin and Hard Spun in the 2007 Breeders' Cup Classic at Monmouth Park. \nTrainer Craig Dollase was noncommittal Wednesday on Awesome Gem, who likely would be the wagering favorite should he start in the Mile. \n"We're keeping our options open, but we may consider it," Dollase said from Del Mar. "He's pretty versatile, this horse; he doesn't need to take the track with him, so to speak. I'll work him here late in the week and that will be the final yea or nay as far as him going."