The Giants were searching for their second Grand Slam in three seasons and had beaten Cardiff in five out of their six meetings on the way to winning the Elite League title and also in the Challenge Cup final in March.
However, the Devils, who are looking for their first trophy in three years, were quick out of the blocks and Martin fired them in front after only 68 seconds.
The rest of the first period was a tight affair with both goaltenders, Ben Bowns from Cardiff and the Giants’ Jackson Whistle, making key saves.
It was in the second period that the Devils seized control against an out-of-sorts Giants side who never reached the heights of their best form shown all season long.
MacDonald rounded off a period of sustained pressure to make it 2-0 and then a pair of goals, nineteen seconds apart, effectively sealed the win.
Both were scored by Sanford and both owed a little bit of luck as on the powerplay his shot deflected off the stick of Giants captain Mark Cooper and then almost immediately, Sanford’s attempted pass hit the skate of Josh Roach.
Both redirections gave Whistle no chance but the Devils had earned their luck. They were by far the hungrier team throughout the game.
With the Giants reeling, O’Brien’s superb solo effort made it 5-0 before the second intermission and ended the game as a contest.
Bowns went on to record the shutout in a man-of-the-match performance.
The defeat will not overshadow another successful campaign for the Giants who won their third league and cup double over the past five seasons to go alongside the Grand Slam of two seasons ago but they were second best to the Devils on this occasion.
