NEW YORK — When the season began, the Phillies had the youngest roster in the majors. And for five months, their impressionable core went through on-the-job training to survive and even thrive at baseball's highest level.

The lessons were mostly what you would expect. For Rhys Hoskins, Scott Kingery, Nick Williams, and Jorge Alfaro, it was recognizing how they were being pitched to differently after two and three times through the league and adjusting accordingly. For starters Nick Pivetta and Zach Eflin, it was holding up to the rigors of a career-high workload. For neophyte reliever Seranthony Dominguez, it was learning how to bounce back after a rough outing.

And considering the Phillies entered this weekend's series here against the New York Mets only 3 1/2 games behind the division-leading Atlanta Braves, it's fair to say that enough of them have passed enough tests along the way to make positive strides in their respective careers.

But there's one thing these young Phillies still have left to learn. They have to figure out how to win.

"Oh, for sure, you have to learn how to win," former Phillies shortstop Jimmy Rollins said the other day. "You have to. This late in the season, it's about the win-loss column, but in the beginning, you have to believe you can win. It's like, 'I know we're going to win.' And once you get that mentality — it starts with the first guy, through the staff, through upper management, to the last guy in the bullpen — you know something good is going to happen. You have to learn how to think, 'I am not going to lose.' "

It's a mentality, Rollins says, and it's learned only through experience. And if the Phillies wind up falling short of making the playoffs in a season in which they were barely expected to contend, well, they can still chalk it up as a learning experience along the way to adopting a winning mentality.

Rollins didn't always have it. After the September rally in 2007 and the World Series championship in 2008 and the five consecutive division titles, it's easy to forget that Rollins, Chase Utley, Ryan Howard, and the others who teamed up for the last great era in Phillies history fell short of the postseason in both 2005 and 2006 because they didn't win enough games down the stretch.

Take 2006, for instance. On Sept. 28, the Phillies were one game behind the Los Angeles Dodgers in the wild-card race with four games to play when they sat through a 4 1/2-hour rain delay in Washington. The game didn't begin until 11:32 p.m. and was played only because the Phils were in playoff contention. But they laid an egg, falling behind early and mustering only five hits in a 3-1 loss to the last-place Nationals that effectively killed their season.

It was through disappointments such as that one, though, that Rollins and the gang learned what it takes to win.

"You fight. We dug in," Rollins said. "You're going to go home anyway, so what the hell do you have to lose? We just kept pushing forward, kept pushing forward, and we finally broke through. And then once we finally got there [to the postseason], we were able to sustain it for a little while."

The Phillies have a few veteran players who can relate.

Veterans like Carlos Santana bring experience to a young roster where the chase for a postseason spot is completely new ground.
CHARLES FOX / Staff Photographer
Veterans like Carlos Santana bring experience to a young roster where the chase for a postseason spot is completely new ground.

Jake Arrieta won a World Series in 2016 with the Cubs, who took an incremental step to a title by losing to the Mets in the NL Championship Series in 2015. Tommy Hunter pitched for an Orioles team that won its division and reached the ALCS in 2014, but only after getting bounced in the division series as a wild-card entrant two years earlier. Carlos Santana went through 85- and 81-win seasons with the Cleveland Indians before getting to Game 7 of the World Series in 2016.

But the large majority of the lineup on a nightly basis is still new to all of this, which is precisely why manager Gabe Kapler has spoken individually with several players to stress the importance of staying relaxed as the stakes get higher.

"One of the things we've stressed recently is, in these times, they kind of get a little bit stressful. But we're going to have fun," Kapler said. "We're going to smile. We're going to laugh."

But Kapler also knows that the only way to deal calmly with pennant race pressure is to experience it.

"If I've seen a 16-inning game, the next time I am taking an at-bat in a 16-inning game, I know what it feels like," Kapler said. "The more experiences we have in any situation, the better equipped we are to handle it the next time. Is that part of learning how to win? I think it is."

These young Phillies might still make the playoffs. Their deficit in the NL East is hardly insurmountable, and the Braves aren't running away and hiding. And if they do get into the postseason tournament, there will be a whole new set of experiences from which to learn.

"It's hope vs.  knowing," Rollins said. "When you hope to win, you kind of hope things go your way, and if they don't, it's kind of like, 'Aw.' When you know you're going to win, you don't know how, but you find that way, and that way comes because you're putting yourself in that position over and over and over again."

The young Phillies are trying to find their way. It's part of the process.

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