Rock Hard Ten was a late bloomer and did not race at age two due to shin splints. At age three, he started late in relation to other three-year-olds. Rock Hard Ten stepped up in class four weeks before the Kentucky Derby in the GI Santa Anita Derby and finished second to Castledale but was disqualified and placed third for interference. Due to the late start in the season and his disqualification, Rock Hard Ten did not have enoughgraded stakes race earnings to qualify for the Kentucky Derby. The owners of Rock Hard Ten waited two weeks later until the Preakness Stakes. In that race, the colt faced the top four finishers from the Derby, including the eventual champion and dual classic winner, Smarty Jones. In the 2004 Preakness Stakes, Rock Hard Ten was fractious behind the gate and difficult to load. When the gates opened, he broke alertly and jockey Gary Stevens placed him fourth in a field of ten runners. On Pimlico's club house turn, jockey Mike Smith aboard Derby runner-up Lion Heart floated Smarty Jones out wide and in turn pushed the others horses even further outside. Rock Hard Ten was the most affected, pushed out to the six path on the turn and fading to seventh. Stevens wrestled with Rock Hard Ten, fighting to hold him back and conserve ground. On the second turn, he and Eddington made a charge at the leaders. The two moved up to challenge Lion Heart at the top of the lane. Rock Hard Ten then passed Lion Heart for the place spot, holding on to earn $200,000 as the Preakness runner-up. Smarty Jones won the race by the widest margin in 130 years at 11-1/2 lengths. Following the Preakness, Rock Hard Ten won the GII Swaps Stakes in July at Hollywood Park and the GI Malibu Stakes in December at Santa Anita Park. Rock Hard Ten Ran in the Belmont
Four-year-old season
At age four, Rock Hard Ten developed physically into one of the largest colts to hit the track in history, standing 17.3 hands. That season, he won the grade two Charles H. Strub Stakes, then one of the biggest prizes for an older horse in the grade oneSanta Anita Handicap, and then the grade two Goodwood Breeders' Cup Handicap. He finished his career with an in-the-money percentage of 82%. Out of eleven starts, he won seven, placed once, and came in third once.