Watch: Capitals clinch playoff berth in most unbelievable way possible

So let's talk about how this happened and why it happened.

There were playoff implications all across the NHL on Tuesday, and this game had some of the biggest. The Capitals were facing a win-and-in situation, while the Flyers needed to win in regulation and hope for the Detroit Red Wings to lose in regulation to the Montreal Canadiens.

As both games neared the end of regulation, the Canadiens had a 4-3 lead on the Red Wings, still giving the Flyers some hope. But because they needed to win in regulation, there was going to be a motivation for them to pull their goalie for an extra skater if the game was tied. 

It was.

So they had no choice but to go for it. It obviously did not work as Oshie scored the winning goal.

That goal helped eliminate the Pittsburgh Penguins (who needed a Washington loss), Philadelphia and Detroit from playoff contention. In a cruel note for Pittsburgh and Detroit, the Flyers had already officially been eliminated from playoff contention just moments earlier when the Red Wings tied their game in Montreal to go to overtime. 

The Red Wings ended up winning in a shootout, completing a second improbable comeback in as many nights. It did not matter as the Capitals' empty-net goal had already secured the eighth playoff spot. 

Adding to the chaos of the Capitals' playoff berth is the fact they finished the regular season by being outscored by 37 goals overall, one of the worst marks for a playoff team in the modern NHL era.