It's pretty common to fall off at the end of the regular season, all the teams who have no chance of moving up or down in their brackets (in order to gain home ice or face a more favorable contender) rest their top talent. The Avs last few games saw their fourth line promoted to first, and lines 2-4 populated with dudes who didn't see any I've time this year. No use in risking injury for games that literally don't matter.
I must've been asleep b/c I didn't recall the Panthers' having slipped so far toward the end of the regular season that Tampa got home ice advantage. Hell, the cats finished only one point ahead of the Sens! Granted, they were missing Tkachuk and Marchand for a good chunk there. Based on how well they turned it around in Tampa, I won't be surprised if they complete the sweep in Sunrise.