LEXINGTON, Ky. - Every so often, a serious horse comes along late to crash the Kentucky Derby party.\nHe's the horse that some futures bettors can't precisely pinpoint but are relying on as their "all others" pick in February and March. In the last 10 years, Derby winners Charismatic and War Emblem were the prototypes, the ones that seemingly came from nowhere to ultimately defeat horses who had been all the rage on the long Derby trail.\nHold Me Back is bidding to join that club. Dismissed and scarcely mentioned after being put away for the winter by Hall of Fame trainer Bill Mott following a disappointing fifth-place finish last November in the Remsen Stakes at Aqueduct, the colt wasn't even an afterthought until making his seasonal debut March 21 in the Lane's End Stakes at Turfway Park.\nBut after Hold Me Back went last-to-first to win the Grade 2 Lane's End with a flourish, he became part of the Derby discussion - although he's still on the fringes. And while Mott and the colt's owner, WinStar Farm, considered going straight to the May 2 Derby - Hold Me Back already has sufficient graded earnings to make the 20-horse cutoff - the more attractive option became the Grade 1, $750,000 Blue Grass Stakes at Keeneland, for which the Giant's Causeway colt will be one of the favorites Saturday.\n"Going into the Derby off the Lane's End, he'd be a bit of an unknown," said Elliott Walden, the former trainer who serves as vice president and racing manager for WinStar. "From an odds perspective, we might've looked up Derby Day and he'd be 30-1 or 40-1, and we really wouldn't know where we were off the one race. It looks like we're going to be 5-2 or 3-1 in the Blue Grass, and we're not going to give that up just to be a longshot to win the Derby."\nPeeking beyond the Blue Grass, which like the Lane's End will be run over Polytrack, Mott said he has few reservations about how Hold Me Back might handle the dirt surface at Churchill Downs. Regardless of what transpires in his fifth career start Saturday, Hold Me Back will enter the Derby with just one dirt race on his past performances - that being a distant fifth in the Remsen. But it must be noted that through the long winter, and until he shipped north for the Lane's End, Hold Me Back trained "very well" over the notoriously deep dirt surface at Payson Park in south Florida, according to Mott.\n"He's trained well enough on the dirt and worked well enough on the dirt," said Mott. "Hopefully he'll run well again Saturday and come out of it good, and we'll be able to move on to Churchill Downs."\nBoth Mott and Walden have fond memories of the Blue Grass. Mott won it 25 years ago with the only horse he has ever run in the race, Taylor's Special, while Walden won it 10 years ago with Menifee.\n"It was one of my biggest thrills," said Mott, adding with a laugh: "He was pretty well tucked up by the time he ran in the Derby." Taylor's Special finished 13th in the Derby in 1984.\nWalden recalled the "great ride" that Pat Day gave Menifee in the 1999 Blue Grass and the "special feeling it gave me to win it" for co-owner Arthur Hancock, who already had won two Kentucky Derbies with Gato Del Sol (1982) and Sunday Silence (1989), "but had never won a Blue Grass. Mr. Hancock was on the board of directors at Keeneland at the time, and the Blue Grass is a race that Kentuckians want to win. It was a special moment in my training career that we were able to do that together."\nFor WinStar, the Versailles, Ky., powerhouse owned by Bill Casner and Kenny Troutt, success in the Blue Grass would perpetuate what has been an incredible run over the last year or so. WinStar owns Well Armed, the romping winner of the $6 million Dubai World Cup on March 28, along with other highly accomplished runners such as Colonel John and Court Vision, the latter in partnership with IEAH Stables.\nHold Me Back, a $400,000 purchase at the 2007 Keeneland September yearling sales, will be ridden in the Blue Grass by Kent Desormeaux, who has won both times he has ridden the colt: an October allowance route over the Keeneland Polytrack, and the Lane's End. Desormeaux has won the Derby three times, including last year with Big Brown.\nHold Me Back, who had his final prerace workout Sunday when breezing five furlongs in 1:00.40 over the Keeneland Polytrack, was one of about 10 3-year-olds expected for the 1 1/8-mile Blue Grass when entries were drawn Wednesday. He figures into an intriguing mix of favorites, along with Charitable Man, Patena, Terrain, and Theregoesjojo.\n"Obviously we'd all like to win the Derby," said Walden, who sent out the Derby runner-up twice (Victory Gallop in 1998 and Menifee in 1999) from three starters before giving up his stable in July 2005. "The second part to this whole equation with Hold Me Back is that even though we thought about going straight into the Derby, two preps with a lightly raced 3-year-old is what really gives us the best chance to win it. Bill and I have a belief that you have to put yourself in the best position possible to have success."