LOUISVILLE, Ky. – Joel Rosario is going so good these days that even when he finishes second, he wins. Rosario was aboard Overwhelming on Monday morning when that 3-year-old maiden served as a workmate for Orb in that colt’s final timed drill at Churchill Downs in preparation for Saturday’s $2 million Kentucky Derby. [DERBY WATCH: Top 20 Kentucky Derby contenders with odds and video] Orb, under exercise rider Jenn Patterson, blew past Overwhelming with incredible ease in midstretch of the half-mile work, and Rosario could only smile as Orb continued to get further and further away from him while galloping out. “I was watching to see him and what he did,” Rosario said of Orb, his mount in the Kentucky Derby. “He really moved well. I think he worked very well. I didn’t know if I was going slow or if he was going fast.” Orb went four furlongs in 47.89 seconds, fast enough – and more importantly easy enough – to make some believe he will be the favorite come Saturday. After riding him in his first five starts – two of which were victories – Rosario was not on Orb for his victories in the Fountain of Youth and Florida Derby. John Velazquez rode Orb in those two races, but Velazquez is committed to Verrazano in the Derby. Rosario called himself “really happy” that trainer Shug McGaughey and the colt’s owners gave him the opportunity to ride Orb again. Rosario, who is 0 for 3 in the Derby, said, “I never thought he was going to be one of the favorites for the Derby.” Orb has done nothing but thrive since coming to Kentucky, similar to Rosario himself. Any horse Rosario rides these days has to be given extra consideration by bettors. The 28-year-old native of Santo Domingo in the Dominican Republic has been on a tear the last 10 days. Since April 18, Rosario has ridden 23 winners from 56 mounts. That includes two five-win days and two four-win days. Rosario won the Keeneland riding title with a spring meet record 38 victories and began the Churchill meet Saturday night with five wins from seven mounts. This, after he won the $10 million Dubai World Cup aboard Animal Kingdom on March 30. “I feel like everything is going good, it’s moving forward,” Rosario said. “Every day, every race I ride, I’ve been given the chance to ride better horses in the race. That makes it easy.” McGaughey, who is also seeking his first Kentucky Derby victory, said he is very happy to have Rosario back on the horse. “His confidence level has got to be through the roof and my confidence level in him is through the roof,” McGaughey said. “He’s a young, energetic rider trying to get accomplished what these guys want to get accomplished.”