Everyone at Victoria Road was expecting Leigh RMI to be cut apart by the Daggers, but instead it was Garry Hill's men that were put to the sword.
Steve Watts and Paul Bruce both put early efforts over the bar before Ian Fitzpatrick troubled the Daggers defence with a free-kick from out on the wing which evaded everyone in the box and skimmed past the post.
Chris Piper missed a golden opportunity when his three touches put him through on goal, but neither he nor Mark Bentley, who nicked the ball off his toe, could find the net.
The deadlock was broken three minutes before half time as Paul Shepherd headed home Andy Roscoe's left-wing cross to wrong-foot Danny Naisbitt.
The second half began in the same vein as the first, with the heavy tackles flying in and not particularly well timed.
Carl Barrowclough then stung Naisbitt's hands with a fierce drive which surely would have sealed the game before play swung to the other end and with a pinpoint cross from Bruce, Watts met it with a firm header in the box, but put it inches wide.
Despite Leigh sitting back, happy to defend their lead, the Daggers struck with ten minutes to go to a Tim Cole header after Bentley had his effort cleared off the line.
But Leigh struck back five minutes later when Naisbitt's clearance deflected back off his own defender and David McNiven ran through to slot home in an unguarded net to cap their victory.