Sintra, dispatched at 12-1, came through a breach on the inside in the stretch and narrowly defeated pace-setting Rockin Ron in the C$615,000 Canadian Pacing Derby final for free-for-allers on Saturday night at Mohawk Racetrack.  The final time was 1:48 1/5. Nirvana Seelster (Trevor Henry) flashed his usual sharp speed away from the starting gate, and he was on top as the 26 second opening quarter, with Rockin Ron (Louis-Philippe Roy), an elimination winner, driving through to secure the pocket in front of All Bets Off (Yannick Gingras) and Sintra (Jody Jamieson).  Rockin Ron would then make his move to the front, popping out of the two-hole to secure the lead well before the 54 second half.  While Rockin Ron was doing that, favored Keystone Velocity (Simon Allard) made an early first-over move out of the fifth position, trapping Sintra at the inside. Rockin Ron kept the tempo fast around the final turn, hitting the three-quarters in 1:21, with Keystone Velocity still four lengths behind him and seemingly stalled from first-up.  Nirvana Seelster had also lost ground, falling 2 1/2 lengths behind, and Sintra was still at the rail with just over five lengths to make up if he wanted to win. Through the stretch Rockin Ron drifted out, but still was well in command, up by nearly three lengths with an eighth of a mile to go.  Sintra began to get motivated at that point, though, and had plenty of room to drive through the inside with Rockin Ron, Nirvana Seelster, and All Bets Off all lugging out.  Rockin Ron tried to find the wire in time, but it was to no avail as Sintra got there by a neck.  McWicked (David Miller) rallied from seventh to third in the final quarter, with All Bets Off and Nirvana Seelster finishing in a dead-heat for the fourth position. "It just worked out," said Jamieson.  "I didn't want to be blasting out to the lead; I just wanted to get to the lead at the wire.  I wasn't sure it was going to work out even at the head of the stretch, but it opened up.  Any kind of trip at all, he just explodes through." Sintra, a 4-year-old gelding by Mach Three, is owned by Menary Racing Inc., Brad Gray, and Michael Guerriero.  This was his 16th career victory, and he has now earned C$882,385.  He returned $27.40 to win in the upset.