There's a clear class difference here. It was shown when the two teams met yesterday and Tampa Bay won by three goals despite going with its backup goalie. Now Andrei Vasilevskiy, who I would argue is the best goalie in hockey, will be back in net. 
The Lightning are 7-1-1 with Vasilevskiy in goal. He has a 1.88 GAA and a .931 save percentage. Tampa Bay hasn't allowed more than two goals in seven of his nine starts.
While the Lightning are already in peak form, the Predators are having a down season going 3-7 in their last 10 games. If you discount a 6-5 overtime victory against the Panthers, the Predators have scored just 14 goals in regulation during their last nine games. 
Tampa Bay ranks fourth in scoring at 3.6 goals per game.