The trip has been planned for weeks and marked on Scott Kingery's calendar for even longer. But the reality won't set in until the Phillies' rookie shortstop actually arrives and looks out over the hills beyond the outfield fence and sees all the players from all the teams from all over the world.

And then, for a few moments Sunday, he might feel as if he's 12 years old again.

"That's when it's going to hit me like, 'That was me. I was here in 2006,' " Kingery said the other day. "It was pretty crazy, so I'm sure it will all come back and hit me once I get there."

Kingery, 24, hasn't been back to Williamsport in 12 years. Not since his Ahwatukee American all-stars, a scrappy group from the Phoenix area, competed in the 2006 Little League World Series, an event that ranks with getting drafted by the Phillies in 2015 and making his major-league debut earlier this year as seminal moments in his baseball career.

When Kingery returns on Sunday, it will be with his Phillies teammates to take part in the MLB Little League Classic. The Phillies and New York Mets will complete their five-game series with a nationally televised game at Bowman Field, but not before they spend several hours meeting, greeting, and interacting with Little Leaguers and watching a game at Lamade Stadium, the same field where Kingery got his first taste of the big time.

It will mark the second year that Major League Baseball will send teams to Williamsport as part of a celebration of youth baseball. And while it will provide players on both teams with a proverbial blast from their pasts, it will mean a little more to Kingery and Mets third baseman Todd Frazier and outfielder Michael Conforto, three of the 13 Little League World Series alumni who have played in the majors this season.

"Right when we got there, sitting on top of that big hill and looking down at the stadium, that was something that just sticks in my mind," Kingery said. "It was incredible to be able to see a field that nice. It was like, 'Oh, that's where we're going to play.' Little League fields, you're playing on fields with a couple bleachers on either side. But this was like a real stadium. You walk in and see the facilities, it took your words away.

"For me, it was the opportunity to play on the biggest stage you could imagine as a 12-year-old. I was a little nervous because I had never played on TV or in front of that many people before. But to be able to see the cameras and do interviews, stuff you've never done before. As a 12-year-old, it was a lot of fun."

>> READ MORE: Phillies beat Mets as Aaron Nola turns in Cy-Young-worthy performance 

It was also a family affair for the Kingerys. Scott, who guessed he was about 4-foot-9 and 79 pounds, batted second and played shortstop alongside his twin brother, Sam, his double-play partner at second base. The team was coached by their father, Tom, who was the Kingery boys' coach through high school and still feels compelled to offer advice and pointers to Scott after watching him play on television.

Tom Kingery keeps old newspaper clippings from the Little League experience in his home in Arizona. Scott is pretty sure there are videotapes there, too, including a clip in which he proudly declares that his favorite player was then-Diamondbacks rookie shortstop Stephen Drew.

"My parents have got that in a file somewhere," said Kingery, who figures he would've been "pretty star-struck" if Drew or any other big-leaguers had shown up to one of his Little League games. "It'll be something good to look back on in 10 or so years."

It's only fitting, then, that Sam and Tom are also traveling to Williamsport to join Scott in his trip down memory lane.

After defeating teams from California and Hawaii to advance to the Little League World Series, Ahwatukee won two of three games in Williamsport but didn't advance to the American semifinal because it lost a head-to-head matchup against the team from Columbus, Ga.,  that wound up winning the world championship.

But neither that nor the fact that he went 0-for-10 in the tournament is what Kingery figures to share whenever any of the Little Leaguers ask for his fondest World Series experience.

"My message, I think, is just to enjoy the moment because baseball can be tough," Kingery said. "At that age, you just want to have fun. It's about being out there and just competing with your friends and having as much fun as possible."

There have been times, Kingery concedes, when his first major-league season hasn't been much fun.

After all but forcing his way onto the Phillies roster with a breakout spring training and securing his spot by signing a six-year, $24 million contract — the largest deal ever given to a drafted player who had not yet made his major-league debut — Kingery hit safely in 11 of his first 18 games. He played all over the field as a super-utilityman and matched the hype befitting a prized prospect.

But Kingery entered the weekend batting .226 with a .268 on-base percentage and six home runs. Among 138 players with at least 400 plate appearances, he ranked 136th with a .598 OPS. And after trading for Asdrubal Cabrera on July 27, the Phillies put Kingery back on the bench after having used him as their primary shortstop.

Encouragement — and coaching tips, of course — still comes almost daily from his father. But that hasn't made the struggles much easier to bear.

>> READ MORE: On Gabe Kapler's Phillies, everyone pitches in 

"He's got some swing tips, but you know, it's tough to listen to him," Kingery said with a laugh. "It's like, 'Hey, it's not that easy, Dad. You can say all that stuff, but it's different when you get out on the field.' He just says, 'You'll bounce back. You've got to learn. You've got to adjust. Stay with who you are and just go have fun.' "

That last bit, the part about having fun, will be Kingery's central theme with the Little Leaguers he meets.

"Even going forward in baseball, if that's going to be your career, try to have as much fun as possible," Kingery said. "There's going to be some tough days, but if you get to go play baseball for a living, I mean, there's nothing better."

Sunday seems like a good day to pause and remember that.