It was because of Mason - who revealed postgame that he started Game 4 after experiencing concussion symptoms the night before the game and went on to outduel Henrik Lundqvist for most of the final four games of the series - that the Flyers even had a sniff at overtime.
"Nobody in this locker room was ready to pack it in," Mason said. "It's tough to put in words right now what you feel. It's a long season. And after one game - boom. It's over."
Mason can wonder because his teammates never quit.
After a 1-7 start to the season and trailing after three games in this Metropolitan Division semifinal series to the Rangers, the Flyers never stopped flying. After all 89 trips on a roller coaster that began in mid-September , the difference between New York and Philadelphia ended up being one goal.
The Rangers squeaked into the second round of the Stanley Cup playoffs with a 2-1 win last night in Game 7, to take the best-of-seven by the most scant of 4-3 margins.
One goal. One swing of the stick. One trickle of a few more inches through Lundqvist's pads on the oh-so-many close calls in the third period. One bitter pill to swallow.
"Game 7. Lose, 2-1. It doesn't get closer than that," captain Claude Giroux said. "We did a good job staying in the battle. On our bench, we were positive that we were going to tie it up. We did get our chances. But it just didn't go in."
Once again down and out after a disastrous second period that saw the Flyers fall into a 2-0 hole when they were outshot, 18-5, by the Rangers, they somehow managed to turn the tide in the third. Jason Akeson cut New York's lead in half in the first 5 minutes of the period - and the Flyers had at least two pucks cut through the crease with eyes on a tied Game 7.
The Flyers ran out of time. The buzzer abruptly sounded on the Flyers' 38th consecutive season without a Stanley Cup, the sound of Frank Sinatra's "New York, New York" filling a quiet locker room overflowing with disbelief.
Akeson admitted it "was a tough way to go out," something coach Craig Berube echoed in his postgame speech to his players before chairman Ed Snider walked around and shook hands to thank them.
"We had a lot of good looks," Jake Voracek said. "We came so close. It was do or die, Game 7, and it came down to one goal."
Berube chalked up the Flyers' loss to a timid middle frame. Mason gave the Flyers the prayer that ultimately went unanswered.
"We didn't initiate enough and play with enough aggressiveness as a team," Berube said. "I think that our game overall, we didn't play our best hockey. Everybody feels lousy, obviously."
With the loss, the Flyers' all-time record in decisive Game 7s dropped to 9-7. It was their first loss in four Game 7 situations, dating back to the 2004 Eastern Conference final against Tampa Bay. Their 2010 comeback against Boston in Game 7 remains the last Game 7 won by the team that was scored upon first, a streak that has now reached 17.
"I'm proud of our players," Berube said. "They went through a lot this year. We were stuck in a hole for a while and they battled out of it. We stuck together and went to a Game 7. They are a bunch of guys with a lot of character."
Even in Game 7, with the stage set for high drama on Broadway, there was very little energy or emotion in the corporate and sterile Garden. In many ways, it was an atypical playoff series for the Flyers.
There was no goaltending controversy. There was no "choking situation." The action on the ice was even devoid of any hatred or vitriol - partly due to the fact that the Rangers were too smart, too disciplined to get caught up in the Flyers' after-whistle shenanigans.
For most of the series - and particularly in the pivotal period of last night's winner-take-all death struggle - the Flyers were simply outdone by the Rangers.
It just happened to play out a lot differently than many imagined: with Mason outplaying Lundqvist, the Flyers' balanced forwards being outscored by New York's bland bunch, and with the Rangers' top defensemen ending up as nonfactors.
The uneasy, nauseating pit the Flyers will feel in their stomachs today while cleaning out their lockers and packing up for another long summer will only be worsened when the second round offers a glimpse of what could have been in sport's ultimate postseason tournament.
The Rangers will open the Metropolitan Division final this weekend in Pittsburgh's Consol Energy Center - the building where the Flyers swept their one, true rival this season. Pittsburgh certainly didn't strike fear into anyone with its first-round performance against Columbus.
All of which leaves the Flyers wondering, like Mason staring into the Garden crowd. So many questions unanswered.
"I think we did think we were better than what we showed," Luke Schenn said. "We definitely never made things easy on ourselves - or gave ourselves a cushion at all. We had to fight until the bitter end. It was a tribute to a lot of the guys and the character we have in here. At the end of the day, one goal is the difference between moving on. It's an empty feeling."
The Flyers killed off their only shorthanded attempt of Game 7, closing the series on a run of 21 consecutive penalties killed against the Rangers . . . Defenseman Kimmo Timonen, 39, might have played the final game of his NHL career. He left Madison Square Garden without speaking to reporters . . . Claude Giroux finished tied with New York's Marty St. Louis and Derek Stepan for the lead in scoring with six points.