Matt's Broken Vow, benefiting from a heads-up ride by Assiniboia's leading jockey Alan Cuthbertson, outran fellow Woodbine invader Bonanza for a 5 1/4-length victory in Monday's $100,000 Manitoba Lotteries Derby. Owned by Robert Mitchell and trained by Josie Carroll, Matt's Broken Vow pressed the slow pace of Mr Exspeedient in the 1 1/8-mile race for 3-year-olds before moving to the lead around the far turn and turning back the brief challenge of Bonanza. "The pace was really slow; he usually lays farther back," said Cuthbertson, who won his first Manitoba Derby. Matt's Broken Vow returned $5.60 as the close second choice behind Bonanza, who went off at even money under rider Simon Husbands. Mr Exspeedient finished third, six lengths behind the runner-up. Completing the order of finish were Colosseum and Ruckus Rules. * Miss Missile ($2.70), trained by Charlie Smith, continued her local dominance with a front-running 4 1/2-length victory under regular rider Rohan Singh in the $50,000 Assiniboia Oaks for 3-year-old fillies. The one-mile Oaks was the third straight stakes score in Winnipeg for Miss Missile, including a win over top mare Polynesian Kitty in the one-mile Canada Day. * Smith came right back in the $50,000 Debutante with Lady Countdown ($3.90), who assumed command shortly after the start and rolled to a convincing 6 1/4-length victory under rider Mark Anderson. Dreamin in Schemin finished second in the 5 1/2-furlong Debutante, with Classy Gem third in the field of six 2-year-old fillies. * Monsoon Rain ($4.40) became a stakes winner for trainer Martin Drexler in the $50,000 Wheat City, scoring by 1 1/4 lengths in the one-mile race for 3-year-olds and upward.