NEW YORK -- Each April 15, Major League Baseball celebrates Jackie Robinson's debut with the Dodgers, marking one of the more special days on the baseball calendar.
Thursday, MLB and the Robinson family kicked off a year-long celebration of the Hall of Famer's life and legacy with a series of events to commemorate what would have been Robinson's 100th birthday.
"It's been a very incredible day," said Sharon Robinson, Jackie's daughter. "It's the beginning of a very full year."
As part of the day's events, a new exhibit titled "In the Dugout with Jackie Robinson" debuted at the Museum of the City of New York, which was attended by Robinson's widow, Rachel, as well as Sharon. Commissioner Rob Manfred was also on hand to take in the exhibit, which features classic photos and artifacts from Robinson's career, as well as original magazine articles.
"I think it's a unique opportunity for our sport to refocus on baseball's finest moment and really, a moment that's of tremendous significance in American history," Manfred said. "We're in with both feet in terms of trying to make the most out of the year and use it as an opportunity to educate and remind people how significant Jackie's accomplishments were."
The year-long celebration will culminate in December with the opening of the Jackie Robinson Museum in the SoHo district of downtown Manhattan.
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"My dad fought his entire life for equity and justice," Sharon said. "To now have a museum that children and adults can come to and learn about the history, but more importantly, a place for them, we hope, to share their ideas on race, religion. Let them really talk about how they're feeling and their experiences."
Early Thursday, Robinson was posthumously presented with the key to the borough of Brooklyn, which was accepted by his granddaughter, Sonya Pankey. Brooklyn borough president Eric L. Adams also issued a proclamation declaring Thursday as "Jackie Robinson Day" in Brooklyn, Robinson's first Major League home with the Dodgers.
"He absolutely deserves it; I'm very proud," Pankey said. "Knowing that this is where it all began for him, it really resonated with me, especially being back in Brooklyn, that they would honor him, I feel like he is definitely here in spirit."
"This is such an amazing and historical day," said New York City council majority leader Laurie Cumbo, who presented the key to Pankey.

Prior to the reading of the proclamation and the presentation of the key, Pankey listened to three local elementary- and middle-school students read their award-winning "Breaking Barriers" essays, part of MLB's annual program in which students from grades 4-9 compose essays to share their personal stories about how they use Robinson's nine values -- citizenship, commitment, courage, determination, excellence, integrity, justice, persistence and teamwork -- to face their own barriers.
"I had to hold back tears," Pankey said. "There's so much pride in watching these kids repeat some of the things that were so important to him. Being able to carry on his legacy and to understand what it means to have impact in society."
"The focus on Jackie, the focus on the values that Jackie stood for, and the writing skills -- it's unbelievable how well-written the essays are from very young people," Manfred said. "The stories are absolutely moving."
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Another one of Robinson's granddaughters, Mehta Robinson, also rang the closing bell at the New York Stock Exchange on Thursday.
MLB's initiatives this year will range from youth engagement activities in cities connected to Robinson's life, to comprehensive support of the Jackie Robinson Foundation's scholarship and education programs.
"The key is to keep the legacy in front of the public, particularly because this year will culminate in the opening of the museum," said Della Britton Baeza, the Foundation's president and CEO. "What's exciting about this being the centennial of Jackie's birth is that we're able to keep his legacy -- all that he's done, from baseball to civil rights activism -- and tell the full story throughout the year and then be able to invite people to the museum to see it done pictorially and with our wonderful artifacts."
"Jackie's message is one that is durable and timeless," Manfred said. "It's an important message for people to be focused on. It was 10 years ago and it is today. Jackie is a symbol of the promotion of diversity and equal opportunity in society. He is the epitome of values like hard work, truthfulness and dedication. He is truly the type of individual that people in America can look up to."
Rachel and Sharon Robinson were given an opportunity to view the "In the Dugout" exhibit at the Museum of the City of New York prior to the grand opening event, taking them back through parts of Jackie's remarkable life.
"It really came down to his own words where he talked about, 'A life is not important except for the impact it has on other lives,'" Sharon said. "That was my dad. He believed in having impact. He taught us as children the importance of making a difference in our community."

Manfred said Thursday's events were not just a reminder of Robinson's impact, but also how meaningful both Rachel and Sharon's involvement with MLB has been in keeping Jackie's legacy alive for future generations.
"Sharon has been a huge asset to baseball over the years; the 'Breaking Barriers' program is durable and really important as part of our programming," Manfred said. "Rachel is an American icon, just a wonderful woman. You can't accomplish the kind of things that Jackie accomplished without a real partner in your life. She was that and she's done an amazing job of carrying on his legacy."
Don't take the Commissioner's word for it. One of the first things patrons will see in the new exhibit is a quote from Robinson himself, in which he stresses the vital role Rachel played in his life.
"Rachel was even more important to my success," reads Robinson's quote, one of many stenciled on the walls of the exhibit. "I know that every successful man is supposed to say that without his wife he could never had accomplished success. It is gospel in my case."