It wasn't always pretty, but the Pittsburgh Penguins are moving on after a heart-pounding overtime win in Game 6 over the Washington Capitals.

Nick Bonino was the hero, with the overtime winner as the Penguins survived a third-period collapse to win 4-3 and punch their ticket to the Eastern Conference finals.

For the Capitals, this is an all-too familiar end to the season. They're out after two rounds despite finishing the regular season with the Presidents' Trophy and looking like one of the best-built teams in these playoffs. It wasn't meant to be yet again for a franchise still seeking its first Stanley Cup.

The series was billed as another Alex Ovechkin vs. Sidney Crosby special, but the series as a whole overshadowed its brightest stars. Game 6 may have been the most thrilling of them all with incredible momentum swings and some of the most mind-boggling moments of these playoffs.

Here are the key takeaways from the Penguins' series-deciding win.

Nick Bonino was the hero as the Penguins eliminated the Capitals. (USATSI)
Nick Bonino is the hero in overtime as the Penguins eliminate the Capitals. (USATSI)

1. The Capitals did not choke so much as the Penguins survived: If there's one word that you absolutely cannot use to describe this Capitals team, it's "choked." They didn't choke. They never gave up in this game or this series. It just wasn't enough.

The Penguins certainly left the door open for their opponents in this one, allowing three goals from late in the second period through the end of regulation. The Penguins took three consecutive delay of game penalties by shooting the puck over the glass from their own zone. Three straight in 2:02, helping the Capitals score the tying goal.

Not only that, but the Capitals had been pressing all period. They put so much pressure on the Penguins late that they were starting to force them into mistakes. The Caps poured 18 shots on net in the final period. They couldn't convert on one more late power play, and then the Penguins were the better team in OT.

Yes, the Capitals came out flat in the game, but they recovered. With the resilience they showed to come back, it's impossible to consider it a choke job. More than anything, the Penguins survived their own miscues and righted the ship for overtime. It was a fantastic game to end the series, as heartbreaking as it might be for Washington.

2. The Kessel-Bonino-Hagelin line is a force to be reckoned with: All four Pittsburgh goals came from their all-college alumni line featuring Phil Kessel, Carl Hagelin and Game 6 hero Nick Bonino. They've been a handful for everyone they play. That proved true again Tuesday night, as they continue to take so much pressure off of Sidney Crosby and Evgeni Malkin to carry the team.

For the longest time, the Penguins were docked for their lack of depth and need for secondary scoring. This line brings it big-time. Kessel scored the first two goals, Hagelin scored the third and Bonino netted the winner in OT with assists from both of them.

With a trio like that, the Penguins have three legitimate lines with excellent scoring capabilities.

3. Justin Williams' excellence in elimination games continues: With a playoff history like that of the Capitals, going out and getting one of the all-time great playoff performers turned out to be one of the savviest offseason buys. After scoring in Game 5, Williams scored once again in Game 6. He now has 14 goals in 19 career elimination games. Mr. Game 7 is basically just Mr. Playoffs. Only two players in NHL history have a higher goal-per-game rate in elimination games than Williams' 0.72 mark: Maurice Richard (0.88) and Pavel Bure (0.80). Stat via NBCSN broadcast.

Here's the goal:

The result may diminish that stat for this particular game, but it's an incredible feat to be that productive in elimination games. It may come in handy next year.

4. The Capitals' penalty kill faltered in the second period: Coming into Tuesday night's contest, the Capitals had allowed only two goals on their previous 40 postseason penalty kills. However, Brooks Orpik took a double-minor for high-sticking Patric Hornqvist in the second period. The Penguins scored twice in 1:33 on the ensuing power play. That was a huge moment, and it made it look like it might not be Washington’s night. Obviously, the tide turned, but the PK faltering at the worst possible time put the Caps in a hole. 

When you consider his three-game suspension and the double-minor he took, Orpik -- a seasoned veteran and former Stanley Cup champion -- did some significant damage to his team in this series.

5. Jay Beagle's goal-line save was the game's most incredible play: Even though it ended up not mattering much for the result, Jay Beagle's miracle dive at the goal line to take a goal away from Patric Hornqvist in OT was one of the most incredible, unlikely plays you'll ever see. This is the type of desperation Washington played with Tuesday night.

Minutes later the game was over. Had the result been different, this would be one of the most memorable plays in Capitals history. Heck, hockey fans everywhere would have talked about it for years.

6. Matt Murray is no ordinary rookie goalie: The Penguins needed their rookie goalie to be solid in Game 6, and was he ever. Murray made 36 saves on 39 shots to earn his seventh postseason win. He's just two wins away from matching his regular-season total from his rookie season. Additionally, the 21-year-old has posted a sparkling .935 save percentage through nine starts, putting him in some elite company that includes such rookies as Braden Holtby, Martin Brodeur and Patrick Roy through his first nine postseason starts (according to NHL Network).

7. The Penguins are perfect in 2015-16 when leading after two periods: Perhaps the Capitals' fate was sealed after the first 40 minutes. The Penguins held a 3-1 advantage after two periods. Throughout this entire season, they have not lost a single game when they lead after two periods. They are 45-0-0 in games they've led after two periods, including 6-0 this postseason. 

8. This was arguably the best Capitals team ever: There's no doubt that this Capitals team will be remembered as one of the best in franchise history. That's what probably makes this loss all the more difficult to swallow. The Caps dominated the regular season, won the Presidents' Trophy, and now for the eighth straight year in the Alex Ovechkin era they have failed to make it past the second round. The streak that dates back to 1998 when the Caps made it to the Stanley Cup Final.

Ovechkin is sure to take a large portion of the blame, but this certainly isn't on him. He played as hard as anyone in the series, notched a pair of assists in Game 6 and was a consistent threat. He is not the reason they lost, even if the narrative will snowball after it looked like this was the year the Caps might finally get over the hump.

The Capitals set a franchise record with 56 wins this season. They were among the league's top goal-scoring teams. Braden Holtby is the presumptive Vezina Trophy winner. Ovechkin won another Rocket Richard Trophy. So many amazing things happened, but this season will be remembered more for how it ended. That's the way this thing works.

With the exception of Game 5, all games in this series were decided by one goal. In the postseason, so often the results come down to a bounce here or there. That's not going to make anyone feel better, but it's the nature of the playoffs.

We'll have more on the end of this memorable Capitals season coming soon.

9. The Penguins-Lightning series is going to be a doozy: While the Penguins will be the heavy favorites, Tampa Bay has shown an ability to push the pace with the best of them. These teams can fly, with the Penguins showing just how much their speed was an advantage in their last two series. The Lightning, meanwhile, will have a few extra days of rest having already dispatched the New York Islanders in five games.

The Penguins have some momentum and some confidence heading into the next series, but they can't take anything for granted. That's especially true if the Lightning get Anton Stralman (leg) and Steven Stamkos (blood clots) back into the lineup.

Get ready for some exciting hockey in that one.