LeBron James says he is "heartbroken" over the death of Kobe Bryant and promises to continue his fellow basketball great's legacy.
Bryant and his daughter Gianna were among nine people killed in a helicopter crash on Sunday.
LA Lakers star James surpassed Bryant to become the NBA's third-highest scorer of all time on Saturday.
James also played alongside Bryant at the 2008 and 2012 Olympics, helping the United States win two gold medals.
"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!" he posted on social media.
"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.
"I'm heartbroken and devastated my brother.
"I promise you I'll continue your legacy man! You mean so much to us all here. 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!!"
Bryant finished his playing career as the Lakers' all-time leading points scorer, and is fourth on the NBA's all-time list with 33,643 points.
In his 1,566th and final game for the Lakers in April 2016 he scored 60 points for the sixth time.
Speaking after the LA Lakers' 108-91 defeat by the Philadelphia 76ers on Saturday, which was the day before Bryant's death, James said: "I'm happy just to be in any conversation with Kobe Bryant.
"One of the all-time greatest basketball players to ever play, one of the all-time greatest Lakers."