With that in mind, the Ospreys have named a strong side - seven of the eight forwards starting this evening feature in the Wales squad for the upcoming Six Nations.
"We may be out of contention but we aim to be competitive in every game we play," said Tandy.
"Looking back at our fixtures throughout this competition, we have been in every game but key moments haven't gone our way and we've paid the price. Those are the margins at this level. We know we need to be more clinical and have to take the opportunities when they present themselves."
Tandy acknowledges the need to make an impression on Leinster, the side top of Pool 1 despite a recent home defeat to Northampton Saints.
"Friday night is Ospreys versus Leinster and regardless of our fate in the competition, or the injuries which are impacting on us, this is a rivalry which has a big history," he added.
"There's no doubt the boys are looking forward to the contest. We still have everything to play for in the PRO12 and the end of season run-in starts here. We need to build momentum, starting on Friday night.
"We'll be looking to the senior players in the squad, those who go away with Wales after the weekend, to put in big performances before they go into camp.
"We're a proud team, with a proud record in the PRO12, and out in Dublin, and the rest of the season starts here."