Grade I winner Lion Heart will race next in the April 10 Toyota Blue Grass Stakes (gr. I) at Keeneland, trainer Patrick Biancone decided Monday, shortly after the chestnut son of Tale of the Cat worked five furlongs in 1:01 2/5 over Santa Anita's fast main track. Regular exercise rider Jean Claude was aboard for the move.Biancone originally had this Saturday's Santa Anita Derby (gr. I) set out for Lion Heart's final Kentucky Derby (gr. I) prep, but decided late last week to consider the Blue Grass partially due to the defection of likely favorite Eurosilver and after considering more time for the Michael Tabor and Derrick Smith color-bearer."He ran a very hard race in his first start this year (a second-place finish to Imperialism in the March 6 San Rafael Stakes)," Biancone said. "The Blue Grass is a better option for him right now because it gives us an extra week to have him ready to run. We don't want to worry about a bounce or anything like that. But he worked good this morning; nice and relaxed. I'm much more happy when he doesn't work too fast. We know he can go fast."Lion Heart is expected to ship to Kentucky with the bulk of Biancone's stable in about a week.Also working Monday was Mercedes Stables' and Madeleine Paulson's lightly raced Rock Hard Ten, who went five-eighths of a mile in :58 2/5 under former jockey Corey Black. The nearly black colt was caught galloping out six furlongs in 1:11 1/5, a time that pleased trainer Jason Orman."That's just how he is," Orman said. "That's his stride."According to Orman, the son of Kris S. will be making his stakes debut in Saturday's Santa Anita Derby, providing he emerges from Monday's work in good order."That's the plan," Orman said. "It was a real good work and I'm happy with how he's doing. If he's good tomorrow and good through the week we're all set for Saturday."Rock Hard Ten has won both of his career starts in maiden and allowance company. With a top effort in the Santa Anita Derby he is expected to head to Louisville and the Run for the Roses.