"This season is all I have left to give," writes Bryant on The Players Tribune in a letter he opens directly to the sport itself with the words, "Dear Basketball."
Bryant is in his 20th season, all with the Lakers since a draft-day trade in 1996 that sent Vlade Divac to the Charlotte Hornets in return for a 17-year old kid taken with the 13th overall pick.
Bryant won five NBA titles. He was still playing at an elite level until April 2013 when he tore an Achilles' tendon. Knee and shoulder injuries have limited Bryant the last two seasons.
"My heart can take the pounding, my mind can handle the grind, but my body knows it's time to say goodbye," writes Bryant.
"I'm ready to let you go," he continues. "I want you to know now, so we can both savor every moment we have left together. The good and the bad. We have given each other all we have."
Bryant, 37, is struggling this season, averaging 15.7 points a game while shooting only 31.5% from the field and 19.5% from three-point range.
The Lakers are in last place in the Western Conference with a 2-13 record.
"You gave a six-year-old boy his Laker dream, and I'll always love you for it," writes Bryant. "But I can't love you obsessively for much longer."
NBA Commissioner Adam Silver issued the following statement regarding Kobe Bryant's announcement:
"With 17 NBA All-Star selections, an NBA MVP, five NBA championships with the Lakers, two Olympic gold medals and a relentless work ethic, Kobe Bryant is one of the greatest players in the history of our game. Whether competing in the Finals or hoisting jump shots after midnight in an empty gym, Kobe has an unconditional love for the game.
"I join Kobe's millions of fans around the world in congratulating him on an outstanding NBA career and thank him for so many thrilling memories."
The Lakers still have 67 games left to play this season, with the regular-season finale on Apr. 13 at Staples Center against the
Coach Byron Scott told reporters before the Lakers' game this evening against the Pacers that he felt "sad" after Bryant told him of his decision.
"We talked about it last night. As I told him, he kind of shocked me when he told me," Scott said. "He's somebody who I truly care about, have a lot of respect for. It's always hard when greatness like Kobe just decides to hang it up.
"He'll get a chance to go around to all these NBA cities and they can really show their appreciation for what he has been able to accomplish in this league has been great."
The Lakers hosted the Indiana Pacers on Sunday night, and Scott said Bryant intended to play, even after playing 34 minutes at Portland on Saturday night.
"I know his purpose is to finish out this season and play," said Scott, Bryant's teammate during the 1996-97 season. "It's always sad when greatness decides to hang it up. … I thought he had at least another year in him."
Scott said it was weird to have that retirement conversation with Bryant.
"It was so matter of fact. And (he) was so at peace. After I thought about it, I felt better about that. It wasn't like he was agonizing over it. He was just like 'Yeah, I'm going to announce I'm retiring.' He just kind of went off from there."
Bryant is expected to have a press conference after Sunday's game.
The Lakers leave Monday for an eight-game road trip that opens in Philadelphia on Tuesday. Bryant attended Lower Merion High, just outside of Philadelphia. "It's home for him. So I think they'll show their appreciation," Scott said about fans in Philadelphia.
Scott was asked what he will remember about Bryant. Scott mentored Bryant as a rookie with the Lakers.
"I can (think) all the way back when he was just this young guy out there at the Forum before the lights came on and before practice was two or three hours away. To this point where he still is at the practice facility in (El Segundo) two or three hours before everybody else getting shots up," Scott said.
Miami guard Dwyane Wade empathized earlier Sunday with Bryant's struggles on the court.
"It's tough to see one of the absolute greatest competitors go through this," Wade told the Associated Press before Bryant made his announcement. "You can put a team around a guy to help a guy, especially late in his career.
"They're just not in position right now to do that. He's won five championships, so no one feels bad for him from that standpoint. But from a standpoint of seeing one of this era's greatest players go out in a rebuilding process, it's tough."
On Instagram Bryant's wife, Vanessa, wrote about his pending retirement: "You can walk away knowing you've always played with everything you have, babe. I'm so proud of you. I'm proud of everything you've given to all of your fans even when you weren't feeling your best. You've always pushed through it because you played for those fans that sacrificed so much to see you play in person. You mean so much to us all. I'm so excited to see what God has in store for us as a family now that one chapter is closing and new ones are opening. We love you!"
Various players around the league responded to Bryant's announcement.
Pau Gasol, who won two championships with Bryant, tweeted: "We have lived incredible moments together on and off the court. Thanks for everything brother! @Kobe Bryant #ThankYouKobe"
Cavaliers guard J.R. Smith: "One of the most under appreciated players to ever play is saying goodbye to the game he gave his all!"
Denver Nuggets center Jusuf Nurkic: "Thanks for everything to the greatest basketball player of all time Kobe Bryant. The game will never be the same!!"
Pelicans guard Eric Gordon: "Much respect to @Kobe Bryant as he announces his retirement after the season. A fierce competitor and one of the greatest to ever do it!"
After the Lakers' 107-103 loss to Indiana, Bryant, as he sat down for his post-game news conference, asked: "So...what's new?"
Bryant said he's completely at peace with his decision to retire. He was smiling, laughing while talking with reporters.
Asked if he might shed a few tears as the end of the season gets closer, Bryant said: "It's not going to happen on the court."
Bryant's advice from Phil Jackson after telling his former coach of his pending retirement: "Break the season up into sections...take it one chunk at a time."
Bryant said he doesn't need to be on Team USA at Olympics next year in Brazil but would "be honored" if it happened.
Bryant on playing in his hometown, on Tuesday, as the Lakers start a long road trip: "It's going to be beautiful. So much of my game was developed in Philadelphia."
And he joked about being a 37-year-old surrounded by all the youth on the Lakers' roster: "I feel like their grandfather. I'm like a triple O.G."
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