TAMPA, Fla. — Champions playing like champions. 

Two-time defending champions playing like they’re as thirsty for the third one as they were for the first two. 

That’s precisely what the Rangers got from the Lightning in Game 3 of the conference final Sunday at Amalie Arena in a stirring 3-2 comeback victory by Tampa Bay, which entered the game down 2-0 in the series and entered the second half of the game down 2-0. 

“Maybe in years past, maybe … maybe panic would have set in at some point,’’ Lightning coach Jon Cooper said. “But definitely not with this group. No question the ‘been-there-before’ has helped our mindset.’’ 

Tampa Bay was there two years ago, winning the Stanley Cup, and it was there a year ago hoisting it again. The Lightning played Sunday like a bunch of players not ready to loosen their grip on the coveted chalice they believe is still theirs. 

Did anyone think the Lightning were going to go away meekly after losing the first two games of this series at Madison Square Garden and coming home for Game 3? 

If anyone thought the Lightning had a weak chin, that thought was dispelled on Sunday. 

Before the game, Rangers winger Ryan Reaves talked about the importance of burying the Lightning while they had the chance Sunday. 

But this Tampa Bay team has a strong pedigree, and now the Rangers have their hands full, beginning with Tuesday’s Game 4 here with the Lightning suddenly energized. 

“We’ve been in spots like this,’’ Cooper said. “The big thing for us was we felt we had a recipe, we just had to stay with it. There were times in this series where we’ve tried to manufacture things that weren’t there that put us on our heels. We weren’t in sync. Our five-on-five game I liked. We just needed to stick with that, stay out of the [penalty] box.’’ 

Tampa Bay was, indeed, the better team at even-strength, which had not been the case in the first two games. 

The Lightning outshot the Rangers, 51-30. 

Champions playing like champions. 

The game-winner was a work of art in front of Rangers goaltender Igor Shesterkin, who never had a chance after Lightning star Nikita Kucherov slipped a nifty backhand pass to Ondrej Palat with Rangers Chris Kreider and Mika Zibanejad losing sight of the puck. 

Palat, one of the unsung stars on the Tampa Bay roster who few speak about often, buried his franchise-record 10th career playoff game-winning goal with 42.1 seconds remaining in regulation. 

Champions playing like champions. 

“He’s a quiet kid. He doesn’t say anything. All he does is give you everything he has on every shift,’’ Cooper said of Palat. 

When you play on the same line as the dynamic Kucherov, who had a hand in all three Tampa Bay goals (scoring the first one on a power-play blast and assisting on the second two), a guy like Palat is going to be overshadowed. 

“He’s got the ability to play that blue-collar game with white-collar players,’’ Cooper said. “That’s a great trait to have. He’s usually the third guy talked about on the lines he plays on, but he comes through.’’ 

The Lightning were in position to win the game with Palat’s heroics after having to kill off a critical four-minute high-sticking penalty by Kucherov on Zibanejad with 9:04 remaining in the game. 

Champions playing like champions — even when it looked grim, down 2-0 halfway through the second period. Though they got a boost when Jacob Trouba was whistled for tripping, negating half of the Rangers’ man-advantage. 

“You get on the bench, you’re down 2-0 in the game and 2-0 in the series you feel the momentum going the other way and it’s certainly not easy,’’ Tampa Bay center Steven Stamkos said. “But that’s what it is to find a way at this time of year, find out which teams can sustain that adversity. We’ve done it for a couple years now and have found a way and [Sunday] was another example. 

“It was about finding a way to just win one game. That’s what we talked about before the game — will your way to a win tonight and then whatever happens, happens. 

“It wasn’t an ideal situation, but there’s no quit in our group.’’ 

Interesting, the “no quit’’ theme has been the Rangers mantra during this Cup playoff run, with T-shirts and posters having been made to commemorate their comeback series wins over Pittsburgh and Carolina before this series. 

Now, the Rangers must deal with a two-time defending Stanley Cup champion that believes again. 

Even up 2-1 in the series entering Tuesday’s Game 4, it’s a dangerous spot. 

“We cannot go ahead and start ordering their Stanley Cup rings, because there is still a long way to go,’’ former Rangers playoff hero Stefan Matteau told The Post over the phone before Game 3. “The Rangers will tell you that first. Nothing has been won. They’ve achieved a lot, but the biggest challenge is yet to come.’’ 

The Rangers got a taste of that challenge Sunday afternoon. It gets tougher Tuesday night.