Taking advantage of a disastrous start for odds-on favorite Shake You Down, Canadian Frontier romped to victory in the $107,700 Bold Ruler Handicap (gr. III) at Belmont Park Saturday.Sent off as the longest shot in the field at 20-1 in his graded stakes debut with Javier Castellano in the irons, Canadian Frontier battled Key Deputy and Jerry Bailey on the front end. He edged in front at the head of the stretch after splits of :22 2/5 and :44 4/5 and drew away to a 3 3/4-length triumph. Shake You Down, ridden by Ramon Dominguez, stumbled coming out of the gate from his rail post position and reared briefly after being bumped soon after. Last down the backstretch, the multiple graded stakes winner was forced to the extreme outside for the stretch run and came up empty. He finished last in the field of six at odds of 4-5. Key Deputy rallied after being passed in the stretch to take second by a nose over First Blush, who finished a neck in front of Secret Run. Aggadan was another neck behind in fifth with Shake You Down 2 1/2 lengths farther behind. The winning time was 1:08 4/5 on a fast surface.Trained by Stanley Hough for owner Mrs. Paul E. Robsham, the 5-year-old horse by Gone West–Borodislew (by Seattle Slew) picked up his fourth career win in nine starts. He was a close fourth in his last start, the Yankee Affair at Gulfstream Park on April 11. The winning purse, $64,620, bumped Canadian Frontier's career earnings to $147,897.Marshall Naify bred Canadian Frontier in Kentucky.He paid $43, $15.40 and $9.70. Key Deputy returned $5.10 and $4.50. First Blush, ridden by Mike Luzzi, was $4.30 to show. The exacta was worth $209.50.