Trainer Larry Jones is still debating whether to run Mark Valeski in the Kentucky Derby on Saturday.

Even a solid workout by the colt on Monday didn't settle things. Named for a longtime friend of owner-breeder and former Kentucky governor Brereton C. Jones, Mark Valeski went five furlongs in 1:00.20, equaling the fastest of 28 drills at that distance at Churchill Downs.

Jones is playing it cautiously, waiting to see how the colt responds over the next two mornings.

"I'm not going to guarantee that we're in or out," he said. "Tomorrow will tell me more, and we'll know really on Wednesday morning when I get on him. Especially if he tries to buck me off, then he's in the (starting) gate."

Mark Valeski was runner-up in his last two races; missing by a nose in the Risen Star Stakes, and by a half-length in the Louisiana Derby.

Trainer D. Wayne Lukas, a four-time Derby winner, is closely monitoring the Mark Valeski developments. He trains Optimizer, who remains on the Derby bubble.

The top 20 entrants based on graded stakes earnings are guaranteed spots in the race. Optimizer is 21st on the list. A defection would put Optimizer, a modest 1 for 9 in his career, and Lukas in the Derby.

"I'd really like to see him get a chance to run," said Lukas, a four-time Derby winner. "One thing about him, he's a true mile-and-a-quarter horse."

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