Ex-NBA player Bo Kimble is pleading with Chris Bosh ... RETIRE IMMEDIATELY ... saying he doesn't want to see Bosh die on the court like his friend and college teammate Hank Gathers.
The Heat shut Bosh down on February 9th when the clotting issues that ended his '14-'15 season returned ... this time showing up in his calf.
Bosh is reportedly unhappy with the decision ... and feels he's healthy enough to resume his playing career.
Kimble -- who was present when Hank Gathers died during a college game in 1990 -- thinks returning to the league is a bad idea for Bosh.
"There are so many other things he could do with his life. Hank Gathers had the same thing, Hank could have been a comedian, and actor or did speaking engagements. It’s not worth the risk. I would just say absolutely not, don’t do it."
Gathers was aware of his heart ailment and decided to keep playing anyway ... and Bo says Chris has the chance to make a decision Gathers couldn't.
"If Hank had the ability to do it again he wouldn't have paid the ultimate price ... I am sure [Bosh] has children and they are going to need their father around as much as possible."
We also spoke to Hank's brother Derrick who echoed Kimble's sentiments.
"To this day I am just getting over the loss of my brother ... just fall back and retire."
FYI, We reached out to Dr. Oz to explain Bosh's condition and why it's so serious -- check out the video.
When in L.A. ... you get in the movies -- just like Clippers star Austin Rivers, who locked up a pretty sweet cameo in the new 'Teenage Mutant Ninja Turtles' movie!
We spoke with Austin -- who's still recovering from that gnarly eye injury he suffered earlier in the NBA playoff -- and he told us he was super stoked to get a role in a scene shot at Madison Square Garden.
So, what's next ... "SPACE JAM 2" -- that is, if producers hit him up for a role.
Charles Oakley says he still has Anthony Mason's back -- and he's going in on Fat Joe for "disrespecting" the NY Knicks legend by naming him as the mystery victim in a Biggie Smalls track.
"You don't talk about a guy after he's deceased," Oakley said ... "definitely disrespectful."
The song in question is Biggie's "I Got a Story to Tell" -- in which the rapper details a night where he was sleeping with the GF of a Knicks player ... and when the player came home, Biggie posed as a burglar and pulled out a gun to rob him to cover up the affair.
Gary Payton wants to bring the NBA back to Seattle -- and he's willing to put his money where his mouth is ... telling TMZ Sports he absolutely wants to be an owner of an expansion team in the Emerald City.
The Hall of Famer was leaving Mastro's Steakhouse in Bev Hills when he told us Seattle "deserves" the NBA -- and put it on NBA commish Adam Silver to make it happen.
As for why GP's so passionate about Seattle -- "That's where I started my career, that's where I became a Hall of Famer."
We also asked Gary how he felt about his son, Gary Payton II, entering the NBA Draft -- and if he expects his kid to share the wealth when he starts making NBA dollars.