Kobe Bryant makes a move. The Portland Trailblazers played the Los Angeles Lakers at the Moda Center on Nov 28, 2015. [Photo/IC]

LOS ANGELES - Kobe Bryant has decided to retire after this season, ending his 20-year career with the Los Angeles Lakers.

The 37-year-old Bryant made the announcement in a post on The Players' Tribune on Sunday. The third-leading scorer in NBA history wrote a poem entitled "Dear Basketball" to announce his decision.

"My heart can take the pounding. My mind can handle the grind. But my body knows it's time to say goodbye," Bryant wrote. "And that's OK. I'm ready to let you go. I want you to know now. So we both can savor every moment we have left together. The good and the bad. We have given each other all that we have."

Bryant went straight from high school in suburban Philadelphia to the Lakers in 1996, and he earned five championship rings and 17 All-Star selections during two decades with the franchise - the longest tenure with one team in NBA history. Bryant also won two Olympic gold medals.

But Bryant's last three seasons have ended early due to injuries, and he played in only 41 games over the previous two years. He has struggled mightily in the first 15 games of this season with mostly young teammates on a rebuilding roster, making a career-worst 32 percent of his shots and dealing with pain and exhaustion every day.

In recent months, Bryant repeatedly said he didn't know whether he would play another season, clearly hoping for a rebound in his health and the Lakers' fortunes.