Following the unexpected death of Kobe Bryant, 41, and his daughter, Gianna Bryant, 13, along with seven other passengers in a helicopter crash on Sunday, NBA superstar LeBron James has broken his silence about the passing of his friend.

James took to Instagram late Monday evening to release a heartfelt tribute. In the post, James revealed his last phone call with Bryant was only hours before his death on Sunday morning, as he prepared to travel from Philly to LA. 

“I’m Not Ready but here I go,” states James. “Man I sitting here trying to write something for this post but every time I try I begin crying again just thinking about you, niece Gigi and the friendship/bond/brotherhood we had!”

“I literally just heard your voice Sunday morning before I left Philly to head back to LA. Didn’t think for one bit in a million years that would be the last conversation we’d have.” 

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I’m Not Ready but here I go. Man I sitting here trying to write something for this post but every time I try I begin crying again just thinking about you, niece Gigi and the friendship/bond/brotherhood we had! I literally just heard your voice Sunday morning before I left Philly to head back to LA. Didn’t think for one bit in a million years that would be the last conversation we’d have. WTF!! I’m heartbroken and devastated my brother!! 😢😢😢😢💔. Man I love you big bro. My heart goes to Vanessa and the kids. I promise you I’ll continue your legacy man! You mean so much to us all here especially #LakerNation💜💛 and it’s my responsibility to put this shit on my back and keep it going!! Please give me the strength from the heavens above and watch over me! I got US here! There’s so much more I want to say but just can’t right now because I can’t get through it! Until we meet again my brother!! #Mamba4Life❤️🙏🏾 #Gigi4Life❤️🙏🏾

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“WTF!! I’m heartbroken and devastated my brother!” James continued.

After paying his respects to Gianna, Kobe Bryant’s wife, Vanessa, and Bryant’s three daughters, James emphasized that he will make sure his friend’s work lives on.

“I promise you I’ll continue your legacy man! You mean so much to us all here especially #LakerNation💜💛.”

Only a day before his death, Bryant went on social media to congratulate LeBron James, who surpassed him on the NBA’s career scoring list. 

“Continuing to move the game forward @KingJames. Much respect my brother. #33644,” Bryant tweeted Saturday night.

James expressed similar sentiments of praise on social media after surpassing Bryant, stating that, “He had zero flaws offensively. Zero.”

BEIJING – AUGUST 08: Basketball player LeBron James of the United States adjust the tie of Olympic teammate Kobe Bryant during a visit by US President George W. Bush on the opening day of the Beijing 2008 Olympic Games on August 8, 2008 in Beijing, China. (Photo by Jamie Squire/Getty Images)

James and Bryant have long been considered two of the top NBA players for more than twenty years and shared a deep bond throughout that time.

In the wake of the tragedy, the Lakers-Clippers game scheduled for Tuesday has been postponed.