Ray Emery started the first three games for Mason, who was out with an upper-body injury. Mason played the final 7:15 in a 4-1 loss Tuesday night.
Mason was just getting warmed up. He played perhaps his best game of the season, shutting down a Rangers team that pressured him with shots all game. He was a wall in the final tense minutes when the Rangers pulled goalie Henrik Lundqvist for the extra attacker.
Dominic Moore scored for the Rangers.
Game 5 is Sunday at Madison Square Garden.
Mason heard a thunderous ovation and chants of "Ma-son! Ma-son!" as he skated off a postseason winner for the first time in his career.
He earned this one.
The Rangers outshot the Flyers 16-6 and dominated a first period that put Mason to work in a hurry. But the Flyers escaped with a 1-1 tie after Jason Akeson's shot off the backboards bounced straight to Read, who beat Lundqvist on his left side for the goal.
"He told me he meant to do that," Read said. "It came right to me. I just had to one-time it. I think Lundqvist got a piece of it but we'll take it."
Voracek redirected Brayden Schenn's shot from the slot past Lundqvist for a power-play goal and a 2-1 lead. Mason had never played with a lead in five career postseason starts.
Mason hadn't started a playoff game in five years since his rookie season with Columbus. The Blue Jackets were swept by Detroit in that series, and the late-season injury against Pittsburgh delayed his Philadelphia postseason debut.
Flyers captain Claude Giroux hasn't scored in the series but his strongest performance came after Game 3's loss when he said, "We're going to tie up the series and go back to New York."
Off they'll go to New York, the series tied.
Giroux limped to the bench after taking a hard hit late in the third. Giroux, third in the NHL with 86 points, had no shots on goal in the first two games and has only two assists through four games.
Moore gave the Rangers a 1-0 lead when he joined the rush out of the penalty box and scored on a wraparound goal 4:38 into the game.
The Rangers won Game 3 on the strength of 28 blocked shots that choked the Flyers out of scoring opportunities. In Game 4, the Rangers pounded Mason with shot after shot, doubling the Flyers' total for most of the first two periods.
Mason was sprawled in the crease stopping several shots and kept the Flyers in a game they desperately needed to win.
Lundqvist, an eight-time All-Star and 2012 Vezina Trophy winner, was stout but betrayed by an offense that couldn't convert open looks.
Notes: The Rangers have scored first in the last three games. ... Flyers D Nicklas Grossmann left the game in the second period with a lower-body injury. ... Lauren Hart, the daughter of longtime former Flyers broadcaster Gene Hart, sang "God Bless America," alternating lyrics with Kate Smith, who was on a video image. Smith's rendition of the song has been a rallying anthem for the Flyers since the mid-1970s. ... Game 6 is Tuesday in Philadelphia.