LOUISVILLE, KY -- One of my favorite parts of Kentucky Derby season is an unpredictable moment. It might happen twice, it might happen six times, in the days leading up to the big event. You see a horse somewhere on the grounds at Churchill Downs and exactly when you're looking at him, this feeling hits you, bam! Now that, you think, is a Derby contender! Some of you are wondering if Churchill's full of 'em leading up to the race, how hard can it be to spot a Derby horse? But I'm not talking about your average made-it-to-the-field runner. I'm talking about the one or two in 20, the colts that are peaking at exactly the right moment, training into the race with the swagger of an athlete who knows he's good. Horsemen know how to spot these signals, and once you've been around high-class runners long enough, you start to recognize them too. It's the way a thoroughbred trains in the mornings, powering over the track, long legs effortlessly gobbling up ground. It's the way he cools out in the shedrow, walking easily along. Sure, sometimes a scrawny little thing jumps up and wins the race. The Derby is anything but a pretty pony contest. It takes guts, heart, determination, willpower, speed, strength, stamina and racing luck to find that winner's circle on the first Saturday in May. But sometimes there's a certain energy around a runner, and his poise and presence hits you like a sign from above. For some fans, the moment comes frequently. Thoroughbreds, after all, are gorgeous creatures. Those of us who cover the game day in and day out, however, become a little more selective. Being around well-bred runners all the time, you become more discerning, harder to please. And that just makes the feeling of wonder all the more meaningful when it arrives. Although Archarcharch, Shackleford and Brilliant Speed might not be the top buzz horses of this year's Derby (they're all in the second tier of regarded runners), they've been three of the best lookers in the bunch this week. On Tuesday, Archarcharch bulled his way through a brisk gallop so quickly that clockers caught it as an official work (four furlongs in 0:52.00, and those who viewed the move could only express their admiration. That same day, Shackleford schooled in the paddock, neck bowed, exuding the energy and confidence that powered him through a Sunday bullet in 0:58.80). The morning before, Brilliant Speed skipped over a sloppy track in the third-fastest of seven moves at the distance (five furlongs in 1:01.20), and it was clear he relished the surface. That these three runners are hitting their best stride at just the right time is obvious to the expert eye. Whether or not one of them will get the pace, the trip and the racing luck needed to win the Derby is anyone's guess. But for the sheer vibe they're exuding leading up to the Derby, all bear watching.