Both sides failed to make last season's final - losing to Leinster and Munster respectively - and the winner of today's clash faces an away match against Munster in this year's semi-final.
The battle could be decided by the boot, with Glasgow's Tommy Hayes coming up against Ulster marksman David Humphreys. Both players are prolific scorers on the international stage and regular post personal tallies of more than 20 points.
In the final semi-final, Cardiff travel to Edinburgh. The winner faces a daunting trip to Neath in the semi-finals.
In captain Todd Blackadder, fellow New Zealander Martin Leslie and
British Lion Simon Taylor, Edinburgh have one of the best backrows in Europe, but they'll need to be on their toes to combat the exciting Cardiff backline.
Cardiff coach Dai Young, who has named himself at tighthead prop thanks to a crippling list of injuries, welcomes back the likes of Rhys Williams, Jamie Robinson and Craig Morgan from international duty.
Despite the pace and flair out wide, Cardiff have failed to score many tries this season - a problem they'll have to fix if they want to return to the Welsh capital victorious.
The match will be a good buildup for both sides, looking ahead to next weekend's third round of the Heineken Cup. Edinburgh host French
heavyweights Toulouse, while Cardiff travel to Northampton.
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