LONDON -- Under a beaming sun, hundreds of primary schoolchildren filed into Hopkins’ Field at Queen Elizabeth Olympic Park at 9:30 on the dot, bounding with a seemingly endless supply of enthusiasm.

Joyful shrieks at the sight of Clark the Cub, the Cubs’ mascot, and cheerful class photos with the World Series trophy kicked off Thursday morning’s MLB First Pitch Festival, where around 500 schoolchildren participated in a day of play and skill development. The event, a celebration in the leadup to the London Series between the Cubs and Cardinals this weekend, represents a cornerstone moment for MLB First Pitch, the grassroots skills program that’s been working to introduce baseball on a widespread scale to the next generation of players.

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“I guess this is three years' worth of work that has led up to this point,” said Ben Ladkin, managing director for MLB Europe. “We’re massively excited -- both to get the teams arriving today, to get this [First Pitch Festival] happening and to get this whole week underway. There’s been a massive amount of preparation that’s gone into it.”

Ladkin joined MLB Europe in 2019, just after the first iteration of the London Series between the Yankees and Red Sox. So he’s been present for First Pitch’s entire life cycle. The program, in its third year, has been dedicated to making baseball a consistent presence in the lives of young children in the UK.

“So the program exists in two forms -- one that we run at schools that is a six-week introduction to baseball,” said Ladkin. “It’s really good fun, just all about having a bit of a hit, having a catch, throwing the ball. All the schools that are here today would have done that nationwide program.

“This year, we’ve had two other First Pitch Festivals, one in Sheffield and one in Cardiff around Play Ball Weekend. Then this one, sort of culminating in the shadow of London Stadium. It’s just about trying to give kids that first experience so they can enjoy the game. And then, hopefully, we can build on that and keep them engaged.”

The participants on Thursday were treated to a few special guests: former MLB players Jake Arrieta, Chase Utley and David Eckstein. The World Series winners went from station to station, helping the kids with their throwing and hitting skills, in the name of spreading the game of baseball.

“Giving these experiences to the youth about the game of baseball is something that’s very important to me,” said Arrieta. “If we can just influence even one kid to take a liking to the game of baseball, then we’ve done our job.”

For Arrieta, being able to look out onto the field Thursday morning and see hundreds of English kids having fun with the sport he loves meant the world to him.

“Taking a chance to experience something new is a hurdle to overcome in its own right,” said Arrieta, who preaches trying new things to his two young children. “Just being out here is a big first step.”

Utley, who has neatly settled into a role as a global ambassador for baseball in his retirement, feels encouraged by the sight of the First Pitch Festival in Stratford, London, on Thursday. He, like many others who are passionate about growing baseball’s reach abroad, understands the importance of showing kids the game at such a young age.

“When you look back at whatever sport you love, and what made you become a fan of it -- that usually starts at an early age,” said Utley. “Whether it’s meeting a professional player, going to a game, or your parents introducing you, there’s a number of different ways you’re introduced to the sport. But those kids always grow up to be very passionate about it.”

In Ladkin’s eyes, Thursday’s First Pitch Festival and the subsequent London Series are just the beginning of plans for exponential growth in baseball in the UK. He wants to continue to build the foundation of youth baseball in concert with the British Baseball Federation, trying to provide an integral first experience to more than 10,000 kids in MLB First Pitch this year. He recognizes that having a strong base of people who enjoy their first taste of the game is the key to growing the game at all levels.

“We’re now well establishing [First Pitch] in a whole group of schools, and we want them to keep doing it year after year,” said Ladkin. “The real focus then comes on with a real club network and how we support that. We want to get more clubs that are able to support young kids as they start that baseball journey, keeping them on it.

“It’s a really long-term project, because we have to be honest, baseball isn’t really a well-established sport over here yet. We’re going to have to build that out, and we’re really excited about that.”