There are three allowances on a 10-race Sunday card at Fair Grounds, but as far as Kentucky Derby watchers are concerned, only one that matters. A chestnut colt named Machen will make the second start of his career in the fifth race, and after earning an eye-popping 95 Beyer Speed Figure in a romping victory in his Jan. 2 debut at the New Orleans track, a similar performance on the stretchout Sunday surely would bump him up a few rungs on everyone’s list of 2011 Derby prospects. “We were nothing short of thrilled with the way the colt ran first out,” said Neil Howard, who trains the homebred colt for the Courtlandt Farms of Donald Adam. “We were in pretty much of a comfort zone with him because he’d had a lot under his belt before that.” Machen won his six-furlong debut by 5 1/2 lengths, despite getting away from the gate a bit slowly. His sire, Distorted Humor, already has a Derby winner in Funny Cide (2003), and his dam, Ready’s Gal, was a multiple graded stakes winner of more than $600,000. Machen is her first foal. Howard, 61, has been enjoying a remarkable career resurgence in recent months, having already won races with six different 3-year-olds at the Fair Grounds meet, including the Lecomte last weekend with Wilkinson. As for upcoming Derby preps, most notably the Grade 2, $300,000 Risen Star Stakes on Feb. 19, “we’ll consider all our options here and elsewhere for all our 3-year-olds, including this colt. Without getting too far ahead of ourselves, things are looking upward.” Machen, with Jamie Theriot back to ride, surely will be a huge favorite when he faces just four other 3-year-olds in the fifth race, a $49,000, first-level allowance at a mile and 70 yards on the main track. In the later Sunday allowances, Illusion of Speed could prove a tough catch when coming shrewdly spotted for a $25,000 tag by Bret Calhoun in a $43,000, optional claiming sprint for statebreds (race 6), while Fist of Rage and Harvest Home look like the top contenders in an overflow field in race 9, a $49,000 grass route being run under a first-level condition. First post is 12:40 p.m. Central, with the fifth race set for 2:38 p.m.