Chipper Jones, 40 years old and nearing retirement, delivered the fatal blow - a three-run homer - on a 95-m.p.h. Papelbon fastball.
Papelbon walked off the field and straight down the dugout steps once the five-run ninth inning was complete. Only Roy Halladay, Kyle Kendrick and Charlie Manuel leaned against the railing until Jones parted a mosh pit to stomp on home plate.
"We won the series but so what?" Manuel said. "We had a chance to sweep them. We need to win all the games we can. That's a tough game. That's hard to swallow."
The manager was both incredulous and resigned. The game should have ended on a bases-loaded Martin Prado ground ball to third. Kevin Frandsen backpedaled and the ball flicked off his glove. He had a play at every base, Manuel said, if he cleanly fielded it. He did not, and Prado had a two-run double.
"The ball was floating there," Frandsen said. "It was on a tee. I didn't make the play. There were no bad hops. Nothing. It was right there."
Up stepped Jones, who whacked his second game-winning homer against the Phillies this season.
"I thought the first one against these guys was a pretty special one," Jones said. "If there is a such a thing as one that is better than that one, this is probably it."
Nineteen minutes after first pitch, the Phillies had batted around and boasted a 5-0 lead. The postseason was a pipe dream long before Sunday, but a victory would have pushed the Phillies to seven games behind the second wild-card berth with 28 games to play and five teams to pass.
"I never think I'm too far out," Manuel said.
That optimism had barely spread during recent weeks, for valid reasons. Sunday was affirmation; these Phillies have spent 91 straight days with a losing record.
"I can't speak for the rest of the team," Papelbon said, "but I haven't sat here and said, 'We need to do this, this and this to get back in the wild card.' I'm just trying to execute my pitches and do my job."
Added Cole Hamels, who allowed three runs in six innings: "That's not in my head. My head is to go out and win a ball game."
Papelbon was ready but did not start the ninth inning of a four-run game. Instead, it was lefthander Jeremy Horst, who had recorded the previous four outs. Jason Heyward, a lefty, led off the ninth with a fly out to center.
Horst remained with light-hitting righties Reed Johnson and Paul Janish next because Manuel was leery of the lefthanded bench bats - Brian McCann, Juan Francisco and Eric Hinske - Atlanta had at its disposal.
Johnson singled. Janish, a .200 hitter, walked. He has walked 15 times this season and seven have been issued by Phillies pitchers. After Papelbon walked Michael Bourn with two outs, Prado chopped one to third and chaos ensued.
"Just catch the damn ball," Frandsen said. "That's all you have to do right there."
His teammates shuffled from the losing clubhouse to a charter flight, an early wake-up call in Cincinnati for holiday baseball, and one day closer to this nightmare's conclusion.
Contact Matt Gelb at email@example.com or follow on Twitter @magelb.