Weld Lands Second American Derby Simple Exchange gave Irish trainer Dermot Weld a second successive win in the American Derby at Arlington on Saturday night.Weld sent Evolving Tactics to take the extended nine-furlong event last year and Simple Exchange produced a game performance to claim the Grade Two race this time.The son of Danehill improved from third to second as he headed for the far turn under Pat Smullen before forging past the ex-John-Gosden-trained Gwaihir.Cool Conductor, the 6-5 favourite, was the only serious threat but Simple Exchange held him by a neck with Toasted a further three-quarters of a length behind.'There´s no point in coming over here with one that´s not going to win,' Smullen told www.thoroughbredtimes.com.'I´ve been very fortunate in that race and I´m glad to have won it again.'Weld, who was recording his third victory in the race after the success of Pine Dance in 2000, believes Simple Exchange is a better horse than Evolving Tactics.'(Simple Exchange) has more talent, more speed, and more improvement in him,' Weld said. 'I think the best is yet to come.'The Moyglare Stud-owned colt will now be aimed at the Grade One Secretariat Stakes at Arlington on August 14.