ST. PAUL, Minn. — Three-year-old colts are making the move toward the Kentucky Derby on Saturday, but a run at the roses doesn’t mean a horse will be here on Derby Day at Churchill Downs in three weeks. It’s often described as a marathon, and how it happens is hardly down to the wire. The colts that do bring their legs to Churchill for Derby Day often do so late in the week, before rain and cold weather descend upon the Kentucky Derby trail.

“We don’t have a drainage system in here, so if there’s no rain in the morning, no chance,” said Mike Willenberg, the official timekeeper for the Preakness Stakes in Baltimore.

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For the Kentucky Derby, four 3-year-old colts have raced in Baltimore in the last two years. This year, the Exeter colt Nyquist came from Kentucky, only to be found bottled up in the Baltimore area. Of course, there’s significant rain forecast for the city on Saturday. What this means for one of Nyquist’s rivals in the Derby is obvious. Calumet Farm will run Native Diver at Pimlico in a race that could benefit from his extra warm-up week.

At Prince of Wales in Toronto, preparation for the all-Canadian Futurity Cup is about as long as it gets. With a long lead-up, and perhaps a little more time to wait for a worthy opponent, Calumet will send out its horse Shaman Ghost on Saturday at the Woodbine Mile. If the Canadian weather cooperates, Sahrado will be running before the mud has entirely gone down in Churchill Downs.

The Provence Stakes in Lexington, a race on the same day as the Keeneland Oaks, has also become a distinct possibility for the Gai Waterhouse-trained Stouffer. However, if Stouffer runs on Saturday, it’s likely to mean a long-ago-post date of March 2, when it was expected the horse would come to Lexington.

“The 3-year-old colts have come down here the last few years, they’ve had a hard time,” said Mike Wybrow, the Oklahoma-bred water level inspector for the Kentucky Derby and Preakness Stakes.

“We try to get them out in time to save the horse in the event that there’s some sort of Mother Nature related shock that might come. You try to lock them in from early on in the morning and try to keep them out as long as possible. You’ve got a horse up here, you’ve got an opportunity to get to Kentucky in a relaxed way.”

Only one of the boys winning this year’s Preakness and Kentucky Derby came from a track in Maryland: Always Dreaming. The first Maryland-bred horse to win in decades came down in a blaze of glory, stunning Las Vegas oddsmakers and the betting public, and leaving everyone wondering if Kentucky Derby was next. History remembers, but the current Derby schedule has been driving the concentration of 3-year-old colts further and further away from the track used to fill the iconic stained glass bay doors of Pimlico and Laurel Park, the former and a member of the Preakness Stakes Inc.’s family since 1919.