"It feels great," said Reinhart, who threaded a shot just under Ilya Samsonov's blocker for the winner. "To be able to complete that comeback in regulation for that crowd tonight was big."
Improving to 15-4-3 and reclaiming the top spot in the Atlantic Division, the Cats had only ever erased a three-goal deficit in the third period to win a game three other times in their history.
"It was impressive," Panthers interim head coach Andrew Brunette said with a smile. "It shows the resilience of the group. … I thought the desperation level went up three or four notches in the third period. It wasn't one guy. It was all four lines, all six D rolling. It was fun to watch."
Of course, in order to pull off such a comeback there needs to be a struggle first.
Giving up a pair of goals 11 seconds apart in the first period, the Panthers fell behind early against the Capitals. Right after Connor McMichael banked in a shot off Sergei Bobrovsky from behind the cage to make it 1-0 at 5:52. Beck Malenstyn scored his first NHL goal to make it 2-0 at 6:03.
Pushing back for the Panthers less than a minute later, Joe Thornton tapped a rebound past Samsonov from right on top of the crease after a shot from Aaron Ekblad to make it 2-1 at 6:55.
Cutting to the net to score another goal for the Capitals in the second period, Lars Eller took a pass from Tom Wilson, flew into the offensive zone, dashed from the left circle into the low slot and lifted a shot past Bobrovsky and into the twine with his backhand to make it a 3-1 game at 6:40.
Padding the lead for Washington, Nick Jensen scored from the high slot to make it 4-1 at 12:40.
"You let in a couple goals and you kind of battle back," Brunette said. "I felt like we were kind of getting our game going in the second half of the first [period]. I thought at the start of the second we started going again, and then it was 3-1, 4-1, and I felt that we were disconnected there for about 10 minutes in the period. Frustration was leaking in a bit, some individualism at times."
Heading into the second intermission, Reinhart said silence spoke volumes in the locker room.
"It was pretty quiet going into the third," he said. "We kind of knew what needed to be done."
Focused on the task at hand, the Panthers then got a spark from their fourth-liners.
After Patric Hornqvist set up Ryan Lomberg for seemingly an empty-net goal to trim the deficit to 4-2 just 3:23 into the third period, Eetu Luostarinen then made it a one-goal game when took a lob pass from Lomberg and beat Samsonov on a shorthanded breakaway to make it 4-3 at 6:09.
"After my goal we were still two goals out and there was still work to be done," Lomberg said when asked about the game's noticeable momentum swing. "But after Luosty's shorthanded goal, we knew that if we stayed with it we would tie it and then eventually get the winner."
Evening things up on the power play later in the period, Sam Bennett set up shop in front of the net and re-directed a shot from Ekblad with his stick blade into the twine to make it 4-4 at 12:01.
Back on the man advantage with less than a minute left in the game after Bobrovsky drew an interference penalty on Malenstyn, Reinhart collected a pass from Huberdeau, who dished out three assists against the Capitals, and sniped a shot past Samsonov to lock in the 5-4 victory.
Falling to 14-4-5, Washington is tied with Florida for the most points in the NHL.
"We have a belief that we can come back, we can score, and we can play at a high tempo," Brunette said of the Panthers, who finish 2-1-0 in their series with the Capitals this season. "It's nice to put this one in the bank. You can reflect on it and say we know what it takes to win."
Looking to build off this latest comeback, the Cats will host the Sabres on Thursday.
Here are five takeaways from Tuesday's win in Sunrise…