So, it turns out Duke of Mischief is more than just a mud freak.\nBesides a narrow win over maiden turf claimers last winter, the only race Duke of Mischief had won coming into the $250,000 Iowa Derby on Friday night at Prairie Meadows was an off-the-turf entry-level route allowance May 30 at Calder. Duke of Mischief went on a slop romp there, winning by more than 11 lengths, but in hindsight, the race looks more like a corner turned than mere mud love.\nDuke of Mischief was far from Florida on Friday night, and the racing surface at Prairie outside Des Moines, Iowa, was dry as a bone. But Duke of Mischief cruised to another open-lengths victory, beating fellow 13-1 shot Soul Warrior by five lengths.\nTerrain, the even-money favorite under Robby Albarado, was injured during the race and had to be euthanized. He suffered fractured sesamoids and a condylar fracture to his right-front leg, according to trainer Al Stall.\nDuke of Mischief ($29.20) broke a half-step slow, and briefly raced near the back of a nine-horse field. But jockey Eibar Coa deftly guided him into position around the first turn, and things went smoothly from there. This was the second straight weekend that Coa had traveled to ride a 3-year-old in a stakes race for Florida-based trainer David Fawkes. And the result Friday at Prairie was as favorable as the one June 20 at Charles Town, where Coa rode Big Drama to victory in the $250,000 Red Legend Stakes for Fawkes.\nDuke of Mischief hasn't done nearly as much as millionaire Big Drama, but he looks all right. Racing inside behind a surprisingly slow pace of 49.13 seconds for the opening half-mile, Coa and Duke of Mischief swung into action midway around the far turn, when Coa left the fence and went up three wide to challenge Soul Warrior and pacesetting Red Lead. Duke of Mischief cornered athletically, but drifted in when Coa shifted his weight to try and get the colt to change leads at the top of the straight. Duke of Mischief quickly straightened out, changed leads, and overpowered his rivals, widening to the finish while stopping the timer in 1:42.26 for 1 1/16 miles.\nThe winner races for Alex and JoAnn Lieblong, Marilyn McMaster, and CLS Racing, and earned $150,000 in prize money.\nSoul Warrior edged Red Lead for second, with 5-2 second-choice Moonport an even third, and Proceed Bee a tough-trip fifth.